Reduction and fusion in high-grade L5-S1 spondylolisthesis by a single posterior approach. Results in 50 patients.

INTRODUCTION: Treatment strategies in high-grade L5-S1 spondylolisthesis are controversial. Reduction of slippage, correction of lumbosacral kyphosis and the necessity of a complementary anterior approach are debated in the literature. The present study reports clinical and radiological outcome for reduction and instrumented fusion on a single posterior approach. MATERIAL AND METHOD: A retrospective study included all consecutive adolescent and young adult patients operated on by a single surgeon (D.C.) for high-grade (Meyerding 3-4-5) L5-S1 spondylolisthesis. The technique consisted in reduction of lumbosacral kyphosis and posterolateral fusion on a single posterior approach without resection of the sacral dome or complementary anterior approach. Only cases of adult ptosis required impacted tibial interbody graft. Clinical complications, radiologic lumbopelvic results and sagittal balance were analyzed at last follow-up. RESULTS: Fifty patients, with a mean age at surgery of 21±11 years, were followed up for a mean 5.5±4.6 years. Mean lumbosacral angle was reduced by 25° (from 76° to 101°; P<0.05), and mean listhesis grade by >50% (from 75% to 23%; P<0.0001), without correction loss at last follow-up. C7 sagittal offset was corrected (from 8° to 4°; P<0.05), with harmonization of lumbar (from 57° to 64°; P<0.001) and thoracic curvature (from 37° to 44°; P=0.1). Seventeen patients (34%) showed postoperative radicular deficit, without sequelae at last follow-up. There were no cauda equina lesions. Bone fusion was achieved in 42 patients (84%), in the same surgical step. After revision by complementary interbody graft, there was no residual non-union. CONCLUSION: Surgery on a single posterior approach gave reliable results in high-grade spondylolisthesis in adolescents and young adults. The technique is not however, free of risk (transient neurologic deficit and non-union), and patients should be forewarned. Complementary interbody graft can be reserved to adult ptosis with incomplete reduction of lumbosacral kyphosis and to revision surgery for non-union. LEVEL OF EVIDENCE: IV, retrospective study.

[Selective and non-invasive monitoring of the posterior columns and pyramidal tract during surgery of the spine and spinal cord]. / Monitorage non invasif et sélectif des cordons postérieurs et de la voie pyramidale pendant les chirurgies du rachis et de la moelle épinière.

For intra-operative neurophysiological monitoring during spine and spinal cord surgery, the challenge is to detect, in real-time, the occurrence of neurological impairment at onset in order to remedy the problem as quickly as possible before it becomes definitely acquired and irreversible. The past three decades were marked by considerable technical progress. Feasibility and reliability have now reached a very high level. A multimodal approach combining simultaneous monitoring of somatosensory and motor pathways has enabled a considerable decline in the rate of false negatives reported in the 80s when somatosensory evoked potentials (SSEP) were monitored alone. Several methods of monitoring are described in the literature. Combining transcranial electric stimulation of muscle motor evoked potentials (mMEP) and cortical SSEP allows non-invasive and selective monitoring of the posterior columns and pyramidal tract. One of the most widely used techniques internationally backed by a broad consensus within the International Society of Intra-operative Neurophysiology (ISIN), this technique remains exceptional in French-speaking countries. We expose here the methodological aspects for the readers of La Revue Neurologique.

Do all Charcot Spine require surgery?

INTRODUCTION: Spinal neuroarthropathy (SNA), also called "Charcot spine", is very uncommon disease of unknown etiology. Kronig first reported this pathology in 1884 on a patient with Tabes dorsalis (also known as syphilitic myelopathy). As syphilis tends to disappear in developed countries, spinal cord lesion is the most frequent etiology of SNA. OBJECTIVES: To describe clinical and radiographic results in 12 patients suffering from spinal neuroarthropathy (SNA). METHODS: Twelve patients diagnosed with SNA were included in the study. All patients were wheelchair users. The average delay between the neurological disease and the diagnosis of SNA was 18 years. All patients were initially treated conservatively. Surgery was only indicated in persistent symptomatic or instable cases, and for infected SNA. Surgery was a circumferential arthrodesis. RESULTS: From 12 patients, with a median follow-up of 4 years, five patients were operated on and 7 patients were still conservatively treated. Two patients with back pain and evolutive destruction were declined for surgery. One suffered of bilateral hip ankylosis and extensive spinal surgery would have confined him to bed, and one due to an evolutive bedsore. One patient improved with a complete regression of back pain. CONCLUSION: Nowadays, surgical treatment is recommended with an extensive and circumferential fusion, in order to prevent relapses. Good radiographic outcome is reported but functional results have not been studied. Natural evolution of SNA remains unknown but can be less disabling than surgery. This pathologic mobility can contribute to patient's autonomy and can therefore be considered as opportune. Conservative therapy can be considered for SNA. LEVEL OF EVIDENCE: Level IV.

Neurological risks in scheduled spinal surgery.

Spinal surgery is a high-risk specialty with an ever-increasing patient volume. Results are very largely favorable, but neurologic damage, the most severe complication, may leave major sequelae, some of which can be life-threatening. Neurologic complications may be classified according to onset (per- vs. postoperative) and surgical site (cervical vs. thoracolumbar). The present paper provides quantitative data for the risks involved. Knowledge of these complications and their risk of onset is the best means of guiding prevention strategies. The spine surgeon is part of a multidisciplinary team, with the radiologist and electrophysiologist, which is able to identify risk factors preoperatively and diagnose neurologic complications per- or postoperatively.

Complications of upper cervical spine trauma in elderly subjects. A systematic review of the literature.

UNLABELLED: The frequency of cervical spine trauma in elderly patients is increasing with most injuries occurring in the upper cervical spine. These fractures are associated with a risk of sometimes life-threatening complications, although very few studies have specifically analyzed this. The goal of this study was to identify the incidence of complications in the literature (mortality and morbidity) following upper cervical spine trauma in elderly patients. METHODS: A systematic search was performed on the MEDLINE database without limiting the search by language or date to identify all studies reporting the rate of complications after upper cervical spine trauma in patients over the age of 60. RESULTS: Twenty-four observational studies were included, four were comparative. These studies included a total of 857 patients, mean age 76. Nearly all traumas were odontoid process fractures, and most were treated surgically (57%). The median mortality rate was 9.2% (Q1-Q3: 2.5-19.6) and the median rate of short-term complications was 15.4% (Q1-Q3: 5.8-26.9). The main late stage complication was nonunion, which developed in a mean 10 to 12% depending on the type of treatment. CONCLUSION: Complications following cervical spine trauma are frequent in elderly patients whatever the type of treatment. Knowledge of the rate of complications in the literature and the potential risk factors is essential for the clinician to improve the information provided to patients and to prevent complications. TYPE OF STUDY: Systematic review of the literature. Level of evidence IV.

[Charcot's disease of the lumbosacral joint in spinal cord injury: a case report]. / Arthropathie neurogène de la charnière lombosacrée chez un paraplégique : à propos d'un cas.

OBJECTIVE: Comment on spinal damage in Charcot's disease. OBSERVATION: We report on a paraplegic patient with T9 spinal cord injury who developed destructive arthropathy of the lumbosacral joint. DISCUSSION: Charcot's disease occurs sporadically during the progression of certain chronic neurological diseases. It affects the limbs and the spine, where it causes major disc and vertebral damage. In cases of spinal cord injury, Charcot's disease must be considered when faced with the appearance of spinal deformity or the aggravation of neurological symptoms. Treatment of Charcot's disease requires spinal osteosynthesis for the relief of neurological compression and the re-establishment of spinal stability.

Spinal and pelvic parameters in Marfan's syndrome and their relevance to surgical planning.

Spinal deformities are a common feature of Marfan's syndrome and can be a significant cause of morbidity. The morphology of the scoliosis associated with this condition was previously described by Sponseller, but no correlation with the pelvic parameters has been seen. We performed a retrospective radiological study of 58 patients with scoliosis, secondary to Marfan's syndrome and related the findings in the thoracolumbar spine to the pelvic parameters, including pelvic version (tilt), pelvic incidence and sacral slope. Our results showed marked abnormalities in the pelvic values compared with those found in the unaffected population, with increased retroversion of the pelvis in particular. In addition we found a close correlation between the different patterns of pelvic parameters and scoliosis morphology. We found that pelvic abnormalities may partially dictate the spinal disorders seen in Marfan's syndrome. Our results supplement the well-established Sponseller classification, as well as stressing the importance of considering the orientation of the pelvis when planning surgery.

[Tibia nonunion after intramedullar nailing for fracture: decortication and osteosynthesis by medial plating]. / Traitement des pseudarthroses de jambe après enclouage centromédullaire: intérêt de la décortication ostéopériostée avec ostéosynthèse par plaque médiale.

PURPOSE OF THE STUDY: Intramedullar nailing is now widely used for fractures of the tibia. Extension of nailing indications to proximal, distal, and comminuted fractures has led to a significant rate of complications. The purpose of this study was to analyze decortication and medial plating for the treatment of tibial nonunion after intramedullary nailing. MATERIAL AND METHODS: Eighteen cases of aseptic tibial nonunion after nailing for fracture were treated in three women and fifteen men, mean age 39 years (19-57). The initial classification was open (n = 8), segmental (n = 3), single-focus (n = 15). The fracture site was inferior (n = 6), middle (n = 7), and superior (n = 2). Primary nailing used reaming in 15 cases (83%), unreamed in 3 (17%) static in 13 and dynamic in 5. Four plaster cabts were also applied. Complications were: infection (n = 1), compartmental syndrome (n = 2), tibial nerve palsy (n = 1), dysesthesia (n = 2), and protrusion of the nail into the knee (n = 1). Dynamization was performed in 11 patients, one with additional bone graft and fibulectomy. Repeated reamed nailing was performed in one patient. Seven nonunions were atrophic and 11 were hypertrophic. There were 13 malpositionings associated with the nonunion. Treatment of the nonunion was performed 300 days on average (90-900) after nailing: cancellous bone graft was associated with decortication in four cases because of bone loss (n = 3) or atrophic nonunion (n = 1). RESULTS: Union rate was 94%. Mean time for union was 108 days (80-180) with no significant difference (Student t-test) between atrophic (119 days) and hypertrophic (103 days) nonunion. Correction of the malposition was incomplete in seven patients, with angular malunion of less than 6 degrees in five patients and greater than 10 degrees in two. One late infection occurred and finally healed after external fixation and antibiotic therapy. No skin necrosis occurred. Five patients had pain on the hardware. Removal was performed in one time and pain resolved. Improvement of knee and ankle stiffness was achieved in all patients. DISCUSSION: This technique has been used in our department since 1967. Different studies have found a union rate ranging from 94% to 100% with this procedure. Intramedullary nailing, sometimes associated with bone graft or decortication, is also used for tibial nonunion with a good rate of union. The main problem of intramedulary nailing for nonunion, as for fracture, is the difficulty in avoiding malunion. Plating a nonunion, as a fracture, enables better reduction. Skin problems can occur with the medial plate if the soft tissues are damaged. This situation is very uncommon in secondary surgery. CONCLUSION: Decortication and medial plating was a safe and efficient treatment for tibia nonunion after failure of intramedullary nailing and allows better reduction and repeated nailing.

Replacement arthroplasty in the weight-bearing shoulder of paraplegic patients.

We review the early results of shoulder arthroplasty in the weight-bearing shoulder of long-term paraplegic patients. We have been unable to find previously published results of this subgroup of shoulder arthroplasty patients in the literature. Five paraplegic, female patients who had undergone shoulder arthroplasty were analyzed. All patients had been prospectively assessed with the American Shoulder and Elbow Surgeons (ASES) function score and the Constant score. The mean age at the time of surgery was 70 years. Three shoulders had full-thickness rotator cuff tears, and two were repaired at the time of shoulder arthroplasty. The mean preoperative Constant score was 30 out of 100, improving to 52 out of 100 at a mean follow-up of 30 months (range, 24-36 months). The mean preoperative ASES function score was 28 out of 55, improving to 37 out of 55. One patient was pain-free after surgery, and the mean postoperative pain score was 10 out of 15. There were no features of progressive radiolucency around the glenoid or the humeral components at last review apart from one case in which glenoid implant migration occurred. In view of the satisfactory improvement in terms of pain, mobility, and independence, we believe that it is reasonable to continue to offer this procedure to this subgroup of patients. We will, however, remain vigilant with regard to any further complications arising in these prostheses in the medium to long term as a result of increased loading.

[Use of combined gallium-technetium scintigraphy to determine the interval before second-stage prosthetic reimplantation in hip arthroplasty infection: a consecutive series of 30 cases]. / Intérêt de la scintigraphie couplée gallium-technétium afin d'optimiser le délai de réimplantation prothétique en deux temps des infections sur arthroplastie de hanche: à propos d'une série continue de 30 cas.

PURPOSE OF THE STUDY: We report a series of 30 consecutive patients with chronically infected total hip replacement in a prospective treatment protocol that included two-stage revision surgery and scintigraphic monitoring. The serial bone scans were used to evaluate the course of infection, but not for diagnosis. Negative scintigraphic results were required before the second-stage prosthesis reinsertion after laboratory, clinical, and radiographic normalization were achieved. MATERIAL AND METHODS: Between 1987 and 1997, we prospectively followed thirty patients, who had a chronically infected hip arthroplasty treated by the conventional two-stage revision procedure using scintigraphic verification. For the present series, negative bone scan results were achieved in the resected hip before reinsertion of the prosthesis in all patients except one. The labels used were in every case gallium-67 and technetium-99m MDP with early and late (after 30 hours) scans. A scintigraphic result was considered positive if more gallium than technetium was fixed at a site. Our conventional medical and surgical protocol consisted of an initial complete excision of all foreign bodies with systematic parenteral administration of two antibiotics after having searched for the causative organism. A spacer was never used. Tibial pin traction was always applied during the duration of drainage of the wound. The antimicrobial regimen was administered to all of these patients for 3 months. The prosthesis was reinserted when C-reactive protein (CRP) levels returned to normal and negative scintigraphic results were obtained after a period with no antibiotic therapy. Reimplantation of the prosthesis was always performed with preventive antibiotic therapy selected according to the susceptibility of the initial organisms and begun after collecting new intraoperative bacteriological culture specimens. This antibiotic therapy was pursued only for the duration of the postoperative drainage. RESULTS: This follow-up based on combined technetium-gallium bone scans demonstrated two major advantages. First, no recurrence of infection was observed except in the single patient for whom the protocol was not observed. The second advantage was to permit nonarbitrary determination of the moment of reimplantation of the prosthesis, as there is no clear consensus regarding the interval before reinsertion in the literature. The patients underwent the second-stage of hip reconstruction after a mean interval of 9 months. The mean delay before negative scintigraphic results was 7 months. DISCUSSION: This method, which determines the optimum delay before reimplantation reducing the risk of reinfection to a minimum, gave promising results in this prospective study of 30 patients.

[Subcutaneous tenotomy of Achille's tendon in adults for ankle stiffness. A review of 80 cases]. / Ténotomie d'Achille percutanée dans les raideurs de cheville de l'adulte. A propos de 80 cas.

PURPOSE OF THE STUDY: Lengthening of Achille's tendon is part of surgical program for ankle stiffness in equinus deformity. Usually this lengthening is done by opened surgery with all the well-knowned advantages in term of adjustment. We used a percutaneous method for Achille lengthening with a two stages tenotomy. The purpose of this study is to evaluate advantages, inconvenients and efficiency of the subcutaneous method versus the open method. MATERIALS AND METHODS: We present a retrospective study of a 80 percutaneous lengthening of Achille's tendon in 78 patients done between August 85 and January 96. All patients who went to surgery during this period were reviewed. Mean age was 36 years old and there was 39 left sides and 41 right sides. We separated the extra-articular stiffness (48 cases) and the intra-articular stiffness (32 cases) because in extra-articular etiology the stiffness is a consequence of a primitive neuro-muscular disease as the ankle joint is healthy. 46 ankles had a past history of surgery. The kind of surgery was directely related to the etiology of the equinus. Most of the time, Achille lengthening was the last time of joint mobilisation. Only 15 times lengthening of the equinus tendon was done isolated. We looked at the early results for all patients and late results were only evaluated for the patients who had an isolated lengthening of the Achille tendon the for stastitical reasons. RESULTS: Median follow-up is two and an half years. There was preoperatively 59 ankles equinus and correction was constantly obtained with surgery postoperative improvment was 12 degrees of dorsal ankle flexion. In sub population of isolated achillus lengthening mean gain is 17 degrees. Only one patient had a per-operative complication with an heel anesthesia. We had no late complication related to the method. DISCUSSION: Results of this reviewal confirms efficency of the percutaneous technique in adult. Litterature is very poor concerning Achille's tendon lengthening in adult surgery. It is a very widelly spread method in children. Only few authors have published about it in adults mainly about hemiplegic patients. Our method saves tourniquet time in heavy ankle surgery. There are no painful and sticky scar. Morbidity is very low because we only had one complication related to the method. Healing up of tendon is very good, all patients being able to rase up on their toes. CONCLUSION: A review of our cases showed us the real efficency of this technique. It's a very simple and quick method giving good results with low morbidity. For us there is no indication of open surgery for achille's tendon lengthening.

[Simple puncture versus trocar puncture biopsy for the bacterial diagnostic evaluation of osteoarticular infections. A prospective study of 54 cases]. / Ponction simple contre ponction biopsie au trocart pour le bilan diagnostique bactériologique des infections ostéo-articulaires. Etude prospective sur 54 cas.

PURPOSE OF THE STUDY: We have performed a prospective study in 54 patients with suspected osteoarticular deep infection. The purpose of the study was to compare notch needle-biopsy versus simple punction in term of bacteriological efficiency. MATERIAL AND METHODS: Among 54 patients (32 males, 22 females), 16 cases of deep infections were proven. There was 29 hips, 17 knees, 6 ankles, 2 elbows and 1 shoulder. Each patient was investigated with simple punction and notch needle-biopsy. Diagnostic value of both methods were evaluated by comparison with results of surgical prelevement which was the gold standard for evaluating both tests. The study was made using usual diagnostic test criteria: sensitivity, specificity, positive predictive value, negative predictive value and also likelihood ratio method. RESULTS: Sensibility for the simple punction was 31.25 per cent and sensibility for notch needle-biopsy was 69 per cent. Specificity for simple punction was 97 per cent but for notch needle-biopsy it was 100 per cent. Positive predictive value was respectively 83.33 per cent for simple punction and 100 per cent for notch needle-biopsy. Negative predictive value was 0.71 per cent for simple punction and 0.31 per cent for notch needle-biopsy. Likelihood ratios for simple punction was 11.87 and likelihood ratios for notch needle-biopsy was infinite. DISCUSSION: Sensibility for notch needle-biopsy of 69 per cent is two time superior to sensibility of simple punction. Notch needle-biopsy had no false positive. It is a completely specific test. Methodology was valuable because all patients who had negative result of non invasive test had no preoperative antibiotherapy, and underwent surgery for bacteriological diagnostic only. CONCLUSION: Notch needle-biopsy is always superior to simple punction. This study leads us to modify our practice. From now on we will never use again simple punction but we will only perform notch needle-biopsy which diagnostical efficiency is superior.

Implementation of the Ottawa ankle rules in France. A multicenter randomized controlled trial.

OBJECTIVES: To assess the impact of the implementation of the Ottawa ankle rules on radiography requests in French hospitals during a 5-month intervention period and the impact of using posters alone to sustain the effect of the rules during a 5-month postintervention period. DESIGN: Multicenter randomized controlled trial preceded and followed by observational studies of radiological practices. SETTING: The emergency departments of 5 Paris university teaching hospitals of the Assistance Publique-Hôpitaux de Paris. PATIENTS: A total of 2218, 1911, and 851 patients-all aged 18 years and older-who were seen for acute ankle or midfoot injuries in emergency departments during preintervention, intervention, and postintervention periods, respectively. INTERVENTION: Implementation of the Ottawa ankle rules by emergency department physicians in the intervention hospitals (using meetings, posters, pocket cards, and data forms). During the postintervention period, posters alone were used to sustain the intervention effect. MAIN OUTCOME MEASURE: Percentage of patients for whom radiography was requested. RESULTS: During the preintervention period, 98% and 98.5% of patients were referred for radiography in the intervention and control groups, respectively. During the intervention period, the mean proportions of patients referred for radiography by physicians was 78.9% in the intervention group and 99% in the control group (P=.03). Between preintervention and intervention periods, a relative reduction of 22.4% (95% confidence interval [CI], 19.8%-24.9%) in radiography requests was observed in the intervention group, while requests increased by 0.5% (95% CI, 0%-1.4%) in the control group. During the postintervention period, the proportion of radiography requests in the intervention hospitals was lower than the proportion observed in the preintervention period (83.1% vs 98%). CONCLUSIONS: Implementation of the Ottawa ankle rules significantly reduced radiography requests in French hospitals. Using a minimal postintervention implementation strategy, the effect of this intervention decreased but persisted after it was discontinued.

Excision of heterotopic ossification around the knee following brain injury.

We present the results of five patients who underwent resection of heterotopic ossification around the knee following traumatic brain injury. All the patients had improved function and no pain at a minimum of 1 year follow up, irrespective of their preoperative neurological status. Our philosophy for such surgery is outlined and, although the surgical goals may seem small, the outcome for any individual patient may be considerable.

A floating prosthesis for radial-head fractures.

We report our experience over seven years with a floating radial-head prosthesis for acute fractures of the radial head and the complications which may result from such injury. The prosthesis has an integrated articulation which allows change of position during movement of the elbow. We present the results in 12 patients with a minimum follow-up of two years. Five prostheses had been implanted shortly after injury with an average follow-up of 49 months and seven for the treatment of sequelae with an average follow-up of 43 months. All prostheses have performed well with an improved functional score (modified from Broberg and Morrey 1986). We have not experienced any of the complications previously reported with silicone radial-head replacement. Our initial results suggest that the prosthesis may be suitable for the early or delayed treatment of Mason type-III fractures and more complex injuries involving the radial head.

[Treatment of comminuted fractures of the lower end of the radius with internal osteosynthesis, traction and early mobilization]. / Traitement des fractures comminutives de l'extrémité inférieure du radius par ostéosynthèse interne, distracteur et mobilisation précoce.

Goals for treatment of comminutive fractures of the distal radius include restoration of the articular profile of the proximal part of the joint, while axial loading forces must be avoided as much as possible to prevent secondary displacement. The choice of an internal fixation protected by an external wrist distractor-fixator, with early activo-passive mobilisation, seems to achieve the goal. Twelve patients with a comminuted fracture of the distal radius, including axial articular impigment displacement were reviewed for this study. All fractures were Frykman's type III, IV, VII or VIII. Distraction was done with a specific external apparatus, allowing an internal fixation, using an anterior plate and posterior Kirschner wires for the more complex cases. Distraction was released at the end of the surgical procedure, while the distractor was left in place. The wrist was mobilised early in the post-operative period, and the distractor was removed two months later. At a mean follow-up of 8.5 months, two patients were still painful. Mean motion of the wrist joint was 115 degrees for flexion-extension and 35 degrees for radio-ulnar deviation. Radiological results were good (10 cases), in both planes sagittal and frontal, and stable with time. The radio-ulnar index was correct in 11 cases. Only two cases of Sudeck's atrophy were noted. Authors use a specific external wrist distractor to obtain and maintain reduction in comminuted fractures of the distal end of the radius, using internal fixation in combination. Early motion of the wrist, protected by the wrist distractor seems to lower rates of Sudeck's atrophy.

[Cotrel-Dubousset instrumentation in the treatment of thoracolumbar and lumbar spine fractures]. / L'instrumentation de Cotrel-Dubousset dans le traitement des fractures de la charnière dorso-lombaire et du rachis lombaire.

Thirty-three thoracolumbar and lumbar spine fractures have been operated on using Cotrel-Dubousset instrumentation. Most were thoracolumbar burst fractures. Regional kyphosis at follow-up was 4 degrees, vertebral kyphosis was 8 degrees. Secondary loss of regional kyphosis was 1 degree, and 10 degrees of vertebral kyphosis. This construct with screws varies according to the level (thoraco-lumbar or lumbar); it seems reliable, as compared with other kinds of internal fixation. Restoring the height of the vertebral body is essential and is the key to a good final result. Addition of a postero-lateral fusion and or a brace did not improve the results.

[Lateral stenosis of the lumbar canal]. / Les sténoses latérales du canal lombaire.

The authors report about 139 cases of nerve root compression due to a lumbar stenosis of the lateral recess. Saccoradiculography seems to be the best examination technique, and the radioclinical agreement is satisfactory. The technique for the surgical treatment and the extent of the release are described. Decompression must involve the symptomatic nerve roots, as well as those who appear to be displaced or amputated on radiculography. The only prognostic element noted in this study is the duration of evolution of preoperative symptoms. Thus the results may be less good for radicular pain lasting for more than one year.