Ludwig Oberkircher

Height restoration and maintenance after treating unstable osteoporotic vertebral compression fractures by cement augmentation is dependent on the cement volume used.

BACKGROUND Two different procedures, used for percutaneous augmentation of vertebral compression fractures were compared, with respect to height restoration and maintenance after cyclic loading. Additionally the impact of the cement volume used was investigated. METHODS Wedge compression fractures were created in 36 human cadavaric vertebrae (T10-L3). Twenty-seven vertebrae were treated with the SpineJack® with different cement volumes (maximum, intermediate, and no cement), and 9 vertebrae were treated with Balloon Kyphoplasty. Vertebral heights were measured pre- and postfracture as well as after treatment and loading. Cyclic loading was performed with 10,000cycles (1Hz, 100-600N). FINDINGS The average anterior height after restoration was 85.56% for Kyphoplasty; 96.20% for SpineJack® no cement; 93.44% for SpineJack® maximum and 96% for the SpineJack® intermediate group. The average central height after restoration was 93.89% for Kyphoplasty; 100.20% for SpineJack® no cement; 99.56% for SpineJack® maximum and 101.13% for the SpineJack® intermediate group. The average anterior height after cyclic loading was 85.33 % for Kyphoplasty; 87.30% in the SpineJack® no cement, 92% in the SpineJack® maximum and 87% in the SpineJack® intermediate group. The average central height after cyclic loading was 92% for Kyphoplasty; 93.80% in the SpineJack® no cement; 98.56% in the SpineJack® maximum and 94.25% in the SpineJack® intermediate group. INTERPRETATION Height restoration was significantly better for the SpineJack® group compared to Kyphoplasty. Height maintenance was dependent on the cement volume used. The group with the SpineJack® without cement nevertheless showed better results in height maintenance, yet the statistical significance could not be demonstrated.

Increased age is not associated with higher incidence of complications, longer stay in acute care hospital and in hospital mortality in geriatric hip fracture patients

The number of agile patients in the 10th decade with a strong need for postoperative mobility will increase in the following decades. The present prospective study sought to prove if very old patients with hip-related fractures are disadvantaged according to incidence of complications, length of ICU and in-hospital stay, and in-hospital mortality. We included 402 patients, age 60 years and older, with hip related fractures. Operative treatment consisted of osteosynthesis or endoprothesis. ASA score, body mass index, Charlson Comorbidity Index, Barthel Index and Mini-Mental-Status were documented. We noted length of in-hospital stay and ICU stay as well as readmission to ICU and complications, including their dispersal according to Clavien-Dindo Classification. After univariate analysis, a multivariate analysis was performed. The examined cohorts were 85 patients aged 60-74 years, 253 75-90 years old and 64 >90 year old patients. In-hospital periods (13-14 days) mean stay on ICU (2 days) and frequency of readmission on ICU did not significantly differ statistically. Most complications were grade II, with comparable frequency and modality, displaying no significant difference throughout age-related groups (p=0.461). In-hospital mortality showing significance (p=0.014) only between 75-89 (4.4%) and >90-year-old (12.5%) cohort. Nevertheless, according to multivariate analysis, including the common risk factors, increased age was not an independent risk factor for dying (p=0.132). Patients at an advanced age with hip-related fractures showed neither a prolonged in-hospital nor ICU stay. There was no significant relation of advanced age to number and type of complications.

Height restoration of osteoporotic vertebral compression fractures using different intravertebral reduction devices: a cadaveric study

BACKGROUND The treatment of osteoporotic vertebral compression fractures using transpedicular cement augmentation has grown significantly during the past two decades. Balloon kyphoplasty was developed to restore vertebral height and improve sagittal alignment. Several studies have shown these theoretical improvements cannot be transferred universally to the clinical setting. PURPOSE The aim of the current study is to evaluate two different procedures used for percutaneous augmentation of vertebral compression fractures with respect to height restoration: balloon kyphoplasty and SpineJack. MATERIALS AND METHODS Twenty-four vertebral bodies of two intact, fresh human cadaveric spines (T6-L5; donor age, 70 years and 60 years; T-score -6.8 points and -6.3 points) were scanned using computed tomography (CT) and dissected into single vertebral bodies. Vertebral wedge compression fractures were created by a material testing machine (Universal testing machine, Instron 5566, Darmstadt, Germany). The axial load was increased continuously until the height of the anterior edge of the vertebral body was reduced by 40% of the initial measured values. After 15 minutes, the load was decreased manually to 100 N. After postfracture CT, the clamped vertebral bodies were placed in a custom-made loading frame with a preload of 100 N. Twelve vertebral bodies were treated using SpineJack (SJ; Vexim, Balma, France), the 12 remaining vertebral bodies were treated with balloon kyphoplasty (BKP; Kyphon, Medtronic, Sunnyvale, CA, USA). The load was maintained during the procedure until the cement set completely. Posttreatment CT was performed. Anterior, central, and posterior height as well as the Beck index were measured prefracture and postfracture as well as after treatment. RESULTS For anterior height restoration (BKP, 0.14±1.48 mm; SJ, 3.34±1.19 mm), central height restoration (BKP, 0.91±1.04 mm; SJ, 3.24±1.22 mm), and posterior restoration (BKP, 0.37±0.57 mm; SJ, 1.26±1.05), as well as the Beck index (BKP, 0.00±0.06 mm; SJ, 0.10±0.06), the values for the SpineJack group were significantly higher (p<.05) CONCLUSION: The protocols for creating wedge fractures and using the instrumentation under a constant preload of 100 N led to reproducible results and effects. The study showed that height restoration was significantly better in the SpineJack group compared with the balloon kyphoplasty group. The clinical implications include a better restoration of the sagittal balance of the spine and a reduction of the kyphotic deformity, which may relate to clinical outcome and the biological healing process.

Cement interdigitation and bone-cement interface after augmenting fractured vertebrae: A cadaveric study

Background The treatment of painful osteoporotic vertebral compression fractures with transpedicular cement augmentation has grown significantly over the last 20 years. There is still uncertainty about long-term and midterm effects of polymethyl methacrylate in trabecular bone. Preservation of the trabecular structures, as well as interdigitation of the cement with the surrounding bone, therefore has been gaining increasing attention. Interdigitation of cement is likely relevant for biological healing and the biomechanical augmentation process. In this study a cutting and grinding technique was used to evaluate the interdigitation for 4 augmentation techniques. Methods By use of a standardized protocol, wedge fractures were created in vertebrae taken from a fresh-frozen spine. Thereafter the vertebrae were assigned to 1 of 4 similar groups with regard to the vertebral size and force required to produce the fracture. The 4 groups were randomized to the following augmentation techniques: balloon kyphoplasty, radiofrequency (RF) kyphoplasty, shield kyphoplasty, and vertebral stenting. Histologic analysis was designed to examine the bone structure and interdigitation after the augmentation. Results For the void-creating procedures, the distance between bone and cement was 341.4 ± 173.7 µm and 413.6 ± 167.6 µm for vertebral stenting and balloon kyphoplasty, respectively. Specifically, the trabecular bone was condensed around the cement, forming a shield of condensed bone. The procedures without a balloon resulted in shorter distances of 151.2 ± 111.4 µm and 228.1 ± 183.6 µm for RF and shield kyphoplasty, respectively. The difference among the groups was highly significant (P < .0001). The percentage of interdigitation was higher for the procedures that did not use a balloon: 16.7% ± 9.7% for balloon kyphoplasty, 20.5% ± 12.9% for vertebral stenting, 66.45% ± 12.35% for RF kyphoplasty, and 48.61% ± 20.56% for shield kyphoplasty. The difference among the groups was highly significant (P < .00001). Conclusions Cavity-creating procedures reduce the cement interdigitation significantly and may accordingly reduce the effectiveness of the augmentation procedures.

Primary stability of three different iliosacral screw fixation techniques in osteoporotic cadaver specimens—a biomechanical investigation

BACKGROUND The incidence of osteoporotic and insufficiency fractures of the pelvic ring is increasing. Closed reduction and percutaneous fixation with cannulated sacroiliac screws is well-established in the operative treatment of osteoporotic posterior pelvic ring fractures. However, osteoporotic bone quality might lead to the risk of screw loosening. For this reason, cement augmentation of the iliosacral screws is more frequently performed and recommended. PURPOSE The aim of the present biomechanical study was to evaluate the primary stability of three methods of iliosacral screw fixation in human osteoporotic sacrum specimens. STUDY DESIGN/SETTING This study used methodical cadaver study. METHODS A total of 15 fresh frozen human cadaveric specimens with osteoporosis were used (os sacrum). After matched pair randomization regarding bone quality (T-score), three operation technique groups were generated: screw fixation (cannulated screws) without cement augmentation (Group A); screw fixation with cement augmentation before screw placement (cannulated screws) (Group B); and screw fixation with perforated screws and cement augmentation after screw placement (Group C). In all specimens both sides of the os sacrum were used for operative treatment, resulting in a group size of 10 specimens per group. One operation technique was used on each side of the sacral bone to compare biomechanical properties in the same bone quality. Pull-out tests were performed with a rate of 6 mm/min. A load versus displacement curve was generated. RESULTS Subgroup 1 (Group A vs. Group B): Screw fixation without cement augmentation: 594.4 N±463.7 and screw fixation with cement augmentation before screw placement: 1,020.8 N±333.3; values were significantly different (p=.025). Subgroup 2 (Group A vs. Group C): Screw fixation without cement augmentation: 641.8 N±242.0 and perforated screw fixation with cement augmentation after screw placement: 1,029.6 N±326.5; values were significantly different (p=.048). Subgroup 3 (Group B vs. Group C): Screw fixation with cement augmentation before screw placement: 804.0 N±515.3 and perforated screw fixation with cement augmentation after screw placement: 889.8 N±503.3; values were not significantly different (p=.472). CONCLUSIONS Regarding iliosacral screw fixation in osteoporotic bone, the primary stability of techniques involving cement augmentation is significantly higher compared with screw fixation without cement augmentation. Perforated screws with the same primary stability as that of conventional screw fixation in combination with cement augmentation might be a promising alternative in reducing complications of cement leakage. These biomechanical results have to be transferred into clinical practice and prove their clinical value.

Effect of Preexisting Cognitive Impairment on In-Patient Treatment and Discharge Management among Elderly Patients with Hip Fractures

Objective: To examine the influence of cognitive impairment on the functional outcomes and complication rates of patients with hip fracture during in-patient treatment. Methods: A total of 402 patients who were surgically treated for hip fractures were consecutively enrolled at a single trauma center. The patients were grouped according to their results on the Mini-Mental State Examination (MMSE), i.e., ≥20 points (group I) and ≤19 points (group II). Complication and in-hospital mortality rates as well as postoperative functional outcomes according to the Barthel Index (BI) were compared between the groups. A multivariate regression analysis was performed to control for additional factors. Results: 33% of the patients had MMSE scores ≤19 points. The complication rates were similar between the groups (p > 0.05). Likewise, the overall in-hospital mortality rates were similar between the patients in group I (4.5%) and those in group II (9.8%; β = 0.218, p < 0.740). Functional outcomes, as assessed by the BI, were lower in group II (β = -0.266, p < 0.001). The patients in group II were transferred to a rehabilitation clinic less frequently (52.3 vs. 76.0%, p < 0.001). Conclusions: Patients with lower MMSE scores are at a higher risk for poorer functional outcomes. Perioperative care should focus on the preservation of functional abilities to protect these patients from an additional loss of independence and disadvantageous clinical course.

Early clinical outcome and complications related to balloon kyphoplasty.

The treatment of painful osteoporotic vertebral compression fractures using transpedicular cement augmentation has grown significantly over the last two decades. The benefits of balloon kyphoplasty compared to conservative treatment remain controversial and are discussed in the literature. The complication rates of vertebroplasty and kyphoplasty are considered to be low. The focus of this study was the analysis of acute and clinically relevant complications related to this procedure. In our department, all patients treated between February 2002 and February 2011 with percutaneous cement augmentation (372 patients, 522 augmented vertebral bodies) were prospectively recorded. Demographic data, comorbidities, fracture types, intraoperative data and all complications were documented. The pre- and postoperative pain-level and neurological status (Frankel-Score) were evaluated. All patients underwent a standardized surgical procedure. Two hundred and ninety-seven patients were treated solely by balloon kyphoplasty; 216 females (72.7%) and 81 males (27.3%). Average patient age was 76.21 years (±10.71, range 35–98 years). Average American Society Anestesiologists score was 3.02. According to the Orthopedic Trauma Association classification, there were 69 A 1.1 fractures, 177 A 1.2 fractures, 178 A 3.1.1 fractures and 3 A 3.1.3 fractures. Complications were divided into preoperative, intraoperative and postoperative events. There were 4 preoperative complications: 3 patients experienced persistent pain after the procedure. In one case, the pedicles could not be visualized during the procedure and the surgery was terminated. One hundred and twenty-nine (40.06%) of the patients showed intraoperative cement leaking outside the vertebras, one severe hypotension and tachycardia as reaction to the inflation of the balloons, and there was one cardiac arrest during surgery. Postoperative subcutaneous hematomas were observed in 3 cases, 13 patients developed a urinary tract infection, and 2 patients died during hospitalization. Twenty-four patients (8.1%) returned because of new pain events and 23 patients reported a new painful fracture. Balloon kyphoplasty is a save and effective procedure to treat patients with painful vertebral compression fractures. Rapid patient mobilization after kyphoplasty, as well as a prompt reintegration into the social environment, are possible. Compared to other surgical procedures, especially in patients with an average age of 75 years, balloon kyphoplasty seems to offer some advantages. However, the procedure still has a potential for serious complications and should be performed by well trained personnel.

Percutaneous dorsal instrumentation for thoracolumbar extension-distraction fractures in patients with ankylosing spinal disorders: a case series.

BACKGROUND CONTEXT Thoracolumbar extension-distraction fractures are rare injuries mainly restricted to patients suffering from ankylosing spinal disorders. The most appropriate surgical treatment of these unstable spinal injuries remains to be clarified. PURPOSE To report on a cohort of 10 patients treated with closed reduction and percutaneous dorsal instrumentation. STUDY DESIGN Case series. PATIENT SAMPLE Ten consecutive patients with ankylosing spinal disorders and thoracolumbar extension-distraction fractures (Type B3 according to the AOSpine Thoracolumbar Spine Injury Classification System). OUTCOME MEASURES Postoperative reduction, alignment, and implant position were analyzed by computed tomography. Loss of reduction was assessed on lateral radiographs by using the Cobb technique. Ambulation ability and pain were assessed at follow-up. METHODS Minimally invasive dorsal percutaneous instrumentation was performed in 10 consecutive patients (3 men, 7 women) with a mean age of 81.5 (range 72-90) years between May 2010 and December 2012. The mean postoperative follow-up time was 7.9 (range 4-28) months. RESULTS All 10 patients were treated with closed reduction and dorsal instrumentation; in no case was conversion to an open approach required. The mean operation time was 60.2 (range 32-135) minutes. None of the patients presented neurologic deficits. Cement-augmented screws were implanted in two cases. Sufficient radiographic correction was achieved in all patients; no case of loss of reduction was noted at final follow-up. In one case, complete hardware removal was performed 9 months after the index operation because of persistent back pain at the level of the implant. One patient died of postoperative inferior vena cava obstruction. At discharge, all patients were able to ambulate without the need for crutches or opioid analgesics. At final follow-up, all patients ambulated with full weight bearing; four patients reported persistent back pain. CONCLUSIONS In fragile patients with ankylosing spinal disorders and thoracolumbar extension-distraction fractures, closed reduction and percutaneous dorsal instrumentation provide a satisfying midterm functional outcome while minimizing perioperative risks compared with conventional dorsoventral procedures.

Fractures of the occipital condyle clinical spectrum and course in eight patients

Introduction: Occipital condyle fractures (OCFs) are considered to be rare injuries. OCFs are now diagnosed more often because of the widespread use of computed tomography. Our aim is to report the incidence, treatment and long term outcome of 8 patients with OCFs. Materials and Methods: All patients presenting with multiple trauma from 1993 to 2006 were analyzed retrospectively. Characteristics and course of the treatment were evaluated. Follow-up was performed after 11,7 years (range 5,9 to 19,3 years). Results: Nine cases of OCF in 8 patients were identified. All injuries resulted from high velocity trauma. The average scores on the ISS Scale were 39,6 (24-75) and 7,3 (3-15) on the GCS. According to Andersons classification, 5 cases of Type III and 4 cases of Type I fractures were identified. According to Tulis classification, 5 cases of Type IIA and 4 cases of Type I were found. Indications for immobilization with the halo-vest were type III injuries according to Andersons classification or Tulis type IIA injuries, respectively. Patients with Tulis type I injuries were treated with a Philadelphia collar for 6 weeks. In one patient with initial complete tetraplegia and one with incomplete neurological deficits the final follow-up neurologic examination showed no neurological impairment at all (Frankel-grade A to E, respectively B to E). At follow-up, 3 patients were asymptomatic. Four patients suffered from mild pain when turning their head, pain medication was necessary in one case only. Discussion: OCFs are virtually undetectable using conventional radiography. In cases of high velocity, cranio-cervical trauma or impaired consciousness, high resolution CT-scans of the craniocervical junction must be performed. We suggest immobilization using a halo device for type III injuries according to Andersons classification or Tulis type IIa injuries, respectively. Patients with Tulis type I injuries should be treated with a Philadelphia collar.

One-Year Outcome of Geriatric Hip-Fracture Patients following Prolonged ICU Treatment

Purpose. Incidence of geriatric fractures is increasing. Knowledge of outcome data for hip-fracture patients undergoing intensive-care unit (ICU) treatment, including invasive ventilatory management (IVM) and hemodiafiltration (CVVHDF), is sparse. Methods. Single-center prospective observational study including 402 geriatric hip-fracture patients. Age, gender, the American Society of Anesthesiologists (ASA) classification, and the Barthel index (BI) were documented. Underlying reasons for prolonged ICU stay were registered, as well as assessed procedures like IVM and CVVHDF. Outcome parameters were in-hospital, 6-month, and 1-year mortality and need for nursing care. Results. 15% were treated > 3 days and 68% < 3 days in ICU. Both cohorts had similar ASA, BI, and age. In-hospital, 6-month, and 12-month mortality of ICU > 3d cohort were significantly increased (p = 0.001). Most frequent indications were cardiocirculatory pathology followed by respiratory failure, renal impairment, and infection. 18% of patients needed CVVHDF and 41% IVM. In these cohorts, 6-month mortality ranged > 80% and 12-month mortality > 90%. 100% needed nursing care after 6 and 12 months. Conclusions. ICU treatment > 3 days showed considerable difference in mortality and nursing care needed after 6 and 12 months. Particularly, patients requiring CVVHDF or IVM had disastrous long-term results. Our study may add one further element in complex decision making serving this vulnerable patient cohort.