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Dive into the research topics where Leonard Bastian is active.

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Featured researches published by Leonard Bastian.


The Lancet | 2009

Efficacy and safety of balloon kyphoplasty compared with non-surgical care for vertebral compression fracture (FREE): a randomised controlled trial

Douglas Wardlaw; Steven R. Cummings; Jan Van Meirhaeghe; Leonard Bastian; John Tillman; Jonas Ranstam; Richard Eastell; Peter Shabe; Karen Talmadge; Steven Boonen

BACKGROUND Balloon kyphoplasty is a minimally invasive procedure for the treatment of painful vertebral fractures, which is intended to reduce pain and improve quality of life. We assessed the efficacy and safety of the procedure. METHODS Adults with one to three acute vertebral fractures were eligible for enrolment in this randomised controlled trial at 21 sites in eight countries. We randomly assigned 300 patients by a computer-generated sequence to receive kyphoplasty treatment (n=149) or non-surgical care (n=151). The primary outcome was the difference in change from baseline to 1 month in the short-form (SF)-36 physical component summary (PCS) score (scale 0-100) between the kyphoplasty and control groups. Quality of life and other efficacy measurements and safety were assessed up to 12 months. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00211211. FINDINGS 138 participants in the kyphoplasty group and 128 controls completed follow-up at 1 month. By use of repeated measures mixed effects modelling, all 300 randomised participants were included in the analysis. Mean SF-36 PCS score improved by 7.2 points (95% CI 5.7-8.8), from 26.0 at baseline to 33.4 at 1 month, in the kyphoplasty group, and by 2.0 points (0.4-3.6), from 25.5 to 27.4, in the non-surgical group (difference between groups 5.2 points, 2.9-7.4; p<0.0001). The frequency of adverse events did not differ between groups. There were two serious adverse events related to kyphoplasty (haematoma and urinary tract infection); other serious adverse events (such as myocardial infarction and pulmonary embolism) did not occur perioperatively and were not related to procedure. INTERPRETATION Our findings suggest that balloon kyphoplasty is an effective and safe procedure for patients with acute vertebral fractures and will help to inform decisions regarding its use as an early treatment option.


Lancet Oncology | 2011

Balloon kyphoplasty versus non-surgical fracture management for treatment of painful vertebral body compression fractures in patients with cancer: a multicentre, randomised controlled trial

James R. Berenson; Robert Pflugmacher; Peter Jarzem; Jeffrey A. Zonder; Kenneth B. Schechtman; John Tillman; Leonard Bastian; Talat Ashraf; Frank D. Vrionis

BACKGROUND Non-randomised trials have reported benefits of kyphoplasty in patients with cancer and vertebral compression fractures (VCFs). We aimed to assess the efficacy and safety of balloon kyphoplasty compared with non-surgical management for patients with cancer who have painful VCFs. METHODS The Cancer Patient Fracture Evaluation (CAFE) study was a randomised controlled trial at 22 sites in Europe, the USA, Canada, and Australia. We enrolled patients aged at least 21 years who had cancer and one to three painful VCFs. Patients were randomly assigned by a computer-generated minimisation randomisation algorithm to kyphoplasty or non-surgical management (control group). Investigators and patients were not masked to treatment allocation. The primary endpoint was back-specific functional status measured by the Roland-Morris disability questionnaire (RDQ) score at 1 month. Outcomes at 1 month were analysed by modified intention to treat, including all patients with data available at baseline and at 1 month follow-up. Patients in the control group were allowed to crossover to receive kyphoplasty after 1 month. This study is registered with ClinicalTrials.gov, NCT00211237. FINDINGS Between May 16, 2005, and March 11, 2008, 134 patients were enrolled and randomly assigned to kyphoplasty (n=70) or non-surgical management (n=64). 65 patients in the kyphoplasty group and 52 in the control group had data available at 1 month. The mean RDQ score in the kyphoplasty group changed from 17·6 at baseline to 9·1 at 1 month (mean change -8·3 points, 95% CI -6·4 to -10·2; p<0·0001). The mean score in the control group changed from 18·2 to 18·0 (mean change 0·1 points; 95% CI -0·8 to 1·0; p=0·83). At 1 month, the kyphoplasty treatment effect for RDQ was -8·4 points (95% CI -7·6 to -9·2; p<0·0001). The most common adverse events within the first month were back pain (four of 70 in the kyphoplasty group and five of 64 in the control group) and symptomatic vertebral fracture (two and three, respectively). One patient in the kyphoplasty group had an intraoperative non-Q-wave myocardial infarction, which resolved and was attributed to anaesthesia. Another patient in this group had a new VCF, which was thought to be device related. INTERPRETATION For painful VCFs in patients with cancer, kyphoplasty is an effective and safe treatment that rapidly reduces pain and improves function. FUNDING Medtronic Spine LLC.


Journal of Orthopaedic Trauma | 2001

Surgical options for the treatment of severe tibial pilon fractures: a study of three techniques.

M. Blauth; Leonard Bastian; C. Krettek; C. Knop; Evans S

Objective To determine whether long-term results of one of three different management protocols for severe tibial pilon fractures offer advantages over the other two. Design In a retrospective study, patients were examined clinically and radiologically after internal fixation of severe tibial plafond fractures (i.e., 92 percent Type C fractures according to the AO–ASIF classification). Setting Department of Traumatology, Hanover Medical School. Level I trauma center. Patients Fifty-one of seventy-seven patients treated between 1982 and 1992 were examined clinically and radiologically at an average of sixty-eight months (range 13 to 130 months) after injury. Interventions The patients were treated in three different ways: primary internal fixation with a plate following the AO–ASIF principles (n = 15), which was reserved for patients with closed fractures without severe soft tissue trauma; one-stage minimally invasive osteosynthesis for reconstruction of the articular surface with long-term transarticular external fixation of the ankle for at least four weeks (n = 28); and a two-stage procedure entailing primary reduction and reconstruction of the articular surface with minimally invasive osteosynthesis and short-term transarticular external fixation of the ankle joint followed by secondary medial stabilization with a plate using a technique requiring only limited skin incisions (a reduced invasive technique) (n = 8). Main Outcome Measurements Objective evaluation criteria were infection rate, amount of posttraumatic arthritis, range of ankle movement, and number of arthrodeses. Subjective criteria were pain, swelling, and restriction of work or leisure activities. Results Because only closed fractures were treated by primary internal fixation with a plate, there was a statistically significant difference (p < 0.005) in the distribution of open fractures between the three treatment groups. Fracture classification in these groups were not significantly different. All but four fractures were classified as Type C lesions according to the AO–ASIF system. The soft tissue was closed in 63 percent (n = 32) and open in 37 percent (n = 19). No significant relationship could be found between the soft tissue damage and degree of arthritis or between the type of surgical treatment and extent of posttraumatic arthritis. However, none of the patients who required secondary arthrodesis (23 percent of all cases) were in the group who had undergone two-step surgery (p < 0.05). The range of ankle movement was much greater in the two-step group than in the others; these patients also had less pain, more frequently continued working in their previous profession, and had fewer limitations in their leisure activities. These differences did not reach statistical significance. The incidence of wound infection did not differ significantly among the three groups. Conclusions On the basis of our results, we now prefer a two-step procedure for the treatment of severe tibial pilon fractures with extensive soft tissue damage. In the first stage, primary reduction and internal fixation of the articular surface is performed using stab incisions, screws, and K-wires. Temporary external fixation is applied across the ankle joint. After recovery of the soft tissues, the second stage entails internal fixation with a medial plate using a reduced invasive technique.


Spine | 2001

Late results of thoracolumbar fractures after posterior instrumentation and transpedicular bone grafting

Christian Knop; Henry F. Fabian; Leonard Bastian; Michael Blauth

Study Design. A retrospective clinical study was performed. Objective. To study clinical and radiologic late results after posterior stabilization of thoracolumbar fractures with internal fixator and interbody fusion via transpedicular bone grafting. Summary of Background Data. The posterior approach, using an internal fixator, is a standard procedure for stabilizing the injured thoracolumbar spine. Transpedicular bone grafting was invented by Daniaux in 1986 for achieving an interbody fusion. Pedicle screw fixation with additional transpedicular fusion has remained controversial because of inconsistent reports and a lack of late results. Methods. Between January 1989 and July 1992, 76 patients with thoracolumbar fractures were operatively treated, and after a mean of more than 3 years, 56 of 62 patients (90%) still alive who had their implants removed were examined. Results. According to the Magerl classification, 33 patients sustained Type A, 13 Type B, and 10 Type C fractures. Three patients with incomplete paraplegia returned to normal. In one case of complete paraplegia, no change occurred. The mean operative time was 3 hours. In this study, two complications (3.6%) were observed: one iatrogenic vertebral arch fracture without consequences and one deep infection. Compared with the preoperative status, follow-up examinations demonstrated permanent physical and social sequelae: The percentage of individuals able to do physical labor was reduced by half (22 to 11 patients), whereas the share of unemployed or retired patients doubled (4 to 8 patients). At the time of follow-up examination, only 21 of 42 patients continued in sports. The assessment of reported problems and functional outcome with the Hannover spine score reflected a significant difference between the status before injury (96.6/100 points) and at the time of follow-up evaluation (71.4/100 points) (P < 0.001). The radiographic assessment in the lateral plane (Cobb technique) demonstrated a significant (P < 0.001) mean restoration from an initial angle of −15.6° (kyphosis) to +0.4°(lordosis). Serial postoperative radiographicfollow-up assessment showed progressive loss of correction. At follow-up examination, a mean difference from the postoperative angle of 10.1° was found (P < 0.001). Compared with the preoperative deformity, a mean improvement of 6.1° (average, −9.7°) at follow-up examination was noted. The addition of transpedicular cancellous bone grafting did not decrease the loss of correction. Computed tomography scans after implant removal were performed in nine cases: Only three of nine patients showed evidence of intervertebral fusion. No correlation could be found between the Magerl classification and radiographic outcome. However, the preoperative wedge angle of the vertebral body correlated significantly with the postoperative loss of reduction. Conclusions. Because of the disappointing results from this study, the authors cannot recommend the additional transpedicular cancellous bone grafting as an interbody fusion technique after posterior stabilization in cases of complete or incomplete burst injury to the vertebral body.


European Spine Journal | 2001

Evaluation of the mobility of adjacent segments after posterior thoracolumbar fixation: a biomechanical study

Leonard Bastian; U. Lange; Christian Knop; Guenter Tusch; Michael Blauth

Abstract. An investigation was conducted into the effects of double-level T12–L2 posterior fixation on the mobility of neighboring unfused segments. The segmental mobility of adjacent segments above and below the fixation in ten cadaveric human thoracolumbar spine specimens was measured before and after fixation by biomechanical testing in flexion, extension, right lateral bending, and right rotation, and the data were compared. In flexion and extension, mobility of the segment above the double-level T12–L2 posterior fixation was significantly increased (P<0.05). In the adjacent segment below the fixation, there was no significant increased mobility after fixation for each moment applied. There is evidence that the adjacent segment above a double-level T12–L2 posterior fixation becomes more mobile, and this may lead to an accelerated degeneration in the facet joints due to increased stress at this point. This could be responsible for symptoms like low back pain after spinal surgery.


Journal of Bone and Mineral Research | 2011

Balloon kyphoplasty for the treatment of acute vertebral compression fractures: 2‐year results from a randomized trial

Steven Boonen; Jan Van Meirhaeghe; Leonard Bastian; Steven R. Cummings; Jonas Ranstam; John Tillman; Richard Eastell; Karen Talmadge; Douglas Wardlaw

Vertebral fractures are often painful and lead to reduced quality of life and disability. We compared the efficacy and safety of balloon kyphoplasty to nonsurgical therapy over 24 months in patients with acute painful fractures. Adults with one to three vertebral fractures were randomized within 3 months from onset of pain to undergo kyphoplasty (n = 149) or nonsurgical therapy (n = 151). Quality of life, function, disability, and pain were assessed over 24 months. Kyphoplasty was associated with greater improvements in Short‐Form 36 (SF‐36) Physical Component Summary (PCS) scores when averaged across the 24‐month follow‐up period compared with nonsurgical therapy [overall treatment effect 3.24 points, 95% confidence interval (CI) 1.47–5.01, p = .0004]; the treatment difference remained statistically significant at 6 months (3.39 points, 95% CI 1.13–5.64, p = .003) but not at 12 months (1.70 points, 95% CI −0.59 to 3.98, p = .15) or 24 months (1.68 points, 95% CI −0.63 to 3.99, p = .15). Greater improvement in back pain was observed over 24 months for kyphoplasty (overall treatment effect −1.49 points, 95% CI −1.88 to −1.10, p < .0001); the difference between groups remained statistically significant at 24 months (−0.80 points, 95% CI −1.39 to −0.20, p = .009). There were two device‐related serious adverse events in the second year that occurred at index vertebrae (a spondylitis and an anterior cement migration). There was no statistically significant difference between groups in the number of patients (47.5% for kyphoplasty, 44.1% for control) with new radiographic vertebral fractures; fewer fractures occurred (∼18%) within the second year. Compared with nonsurgical management, kyphoplasty rapidly reduces pain and improves function, disability, and quality of life without increasing the risk of additional vertebral fractures. The differences from nonsurgical management are statistically significant when averaged across 24 months. Most outcomes are not statistically different at 24 months, but the reduction in back pain remains statistically significant at all time points.


European Spine Journal | 2002

Complications in surgical treatment of thoracolumbar injuries.

Christian Knop; Leonard Bastian; Uta Lange; M. Oeser; Zdichavsky M; Michael Blauth

Abstract. The range of surgical methods for operative treatment of thoracolumbar injuries, with their different ways of approach, grafts and techniques, remains wide. The authors present sources of error and specific complications based on their own experience and on the results of a multicenter study of the Spine Study Group of the German Trauma Association (DGU). A systematic overview of possible mistakes and complications is first presented in anatomical order. A detailed analysis is then presented of the complications reported in a multicenter study, carried out prospectively between 1994 and 1996, on 682 patients operated for acute traumatic injuries of the thoracolumbar spine. In 101 cases (15%) at least one complication occurred intra- or postoperatively. In 41 patients (6%) a revision was performed, and in 60 patients (9%) complications without operative revision were observed. These complications were analysed according to the chosen method of initial treatment.


Journal of Bone and Mineral Research | 2006

Oncogenic osteomalacia: exact tumor localization by co-registration of positron emission and computed tomography.

Eric Hesse; Eckart Moessinger; Herbert Rosenthal; Florian Laenger; Georg Brabant; Thorsten Petrich; Klaus Gratz; Leonard Bastian

In oncogenic osteomalacia, the causative tumor is almost always difficult to find. A novel diagnostic approach is presented that facilitates a precise and rapid localization of the associated lesion by PET‐CT co‐registration using the radiotracer 68Ga‐DOTANOC.


Clinical Orthopaedics and Related Research | 2004

New indications for computer-assisted surgery: tumor resection in the pelvis.

T. Hüfner; Mauricio Kfuri; Michael Galanski; Leonard Bastian; Martin Loss; Tim Pohlemann; Christian Krettek

The resection of recurrent malignant pelvic tumors was supported by a commercially available navigation system in three patients. Preoperatively three-dimensional images from the pelvis were obtained by computed tomography or magnetic resonance imaging to identify the tumor extension. During surgery navigated tools oriented the surgeon to excise the tumor with adequate virtual margins. Navigation was helpful for tumor identification in one patient with a recurrent presacral mesenchymal chondrosarcoma. In the other two patients the tumor resection in the bone was done with three-dimensional observation of the osteotomies in the sacrum. In all three patients the histopathologic analysis confirmed that the neoplasms were excised accurately within their margins. We think that computer-assisted surgery is a potential method to increase the accuracy of tumor resections.


European Spine Journal | 2000

Three-dimensional motion analysis with Synex. Comparative biomechanical test series with a new vertebral body replacement for the thoracolumbar spine.

C. Knop; Uta Lange; Leonard Bastian; M. Blauth

Abstract The authors present a new implant for vertebral body replacement in the thoracic and lumbar spine. Synex is a titanium implant designated for reconstruction of the anterior column in injury, post-traumatic kyphosis or tumour of the thoracolumbar spine and must be supplemented by a stabilizing implant. After positioning, the implant is distracted in situ, thus ensuring best contact with adjacent end-plates and three-dimensional (3D) stability, and minimizing the possibility of secondary dislocation or loss of correction. We compared the effectiveness of the Synex implant with that of the “Harms cage” (MOSS) in combination with two alternative stabilizing instrumentations: the USS and Ventrofix. In a 3D spinal loading simulator, we determined the bisegmental (T12–L2) neutral zone (NZ), elastic zone (EZ), and range of motion (ROM) of 12 human cadaveric spines. After corpectomy of L1, we tested the four possible combinations of stabilizing instrumentation and vertebral replacement implant: USS/Synex, USS/MOSS, Ventrofix/Synex, Ventrofix/MOSS. We analysed the differences between each of the instrumentations as well as differences compared to the intact spine. Comparing the two stabilizing implants, a significantly higher stability was achieved with the USS for flexion, extension, and lateral bending, regardless of whether Synex or MOSS was used as vertebral body replacement. No differences were observed for axial rotation. In addition, no implant combination was able to restore the rotational stability of the intact spine. Comparing the vertebral body replacing implants, significantly higher stability was noted with Synex in combination with USS for extension, lateral bending, and axial rotation. No differences between Synex and MOSS were observed in combination with Ventrofix. Posterior fixation was found to offer superior stability compared to anterior fixation. Synex was at least comparable to MOSS for suspensory replacement of the vertebral body in the thoracolumbar spine. The increased biomechanical stability demonstrated for Synex suggests that a more rigid construction would also be achieved in vivo. When using MOSS in combination with posterior stabilization, the induction of intervertebral compression via the posterior fixator is recommended. This surgical step was not necessary with Synex.

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Steven Boonen

Katholieke Universiteit Leuven

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Michael Blauth

Innsbruck Medical University

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