[Case report of an osseous (and lymphogenic) thymic carcinoma in an adult]. / Kasuistik eines ossär (und lymphogen) metastasierten Thymuskarzinoms beim Erwachsenen.

A Thymic carcinoma in adults is rare. We present the case of a 47-year-old man, who was treated conservatively for spondylolisthesis L5/S1 in our institution for several years. In the further course, the patient complained about pain exacerbation with acute lower back pain. Cross-sectional scanning showed a tumor of the lumbar vertebral body three. A biopsy of this mass revealed a metastatic thymic carcinoma of the squamous cells. After palliative therapy, the patient died 9 months after initial diagnosis.

Prolonged suppressive antibiotic therapy is successful in the management of prosthetic joint infection.

INTRODUCTION: Prosthetic joint infection (PJI) remains one of the major challenges facing orthopaedic surgeons. There is a paucity of evidence on non-operative management of PJI. We present the results of prolonged antibiotic suppression therapy (PSAT) in PJI from a single centre. METHODS: A retrospective study was performed. Twenty-six patients were included. Two patients were excluded due to the lack of follow-up data. Failure was defined as admission for sepsis from the joint or amputation. RESULTS: Average age was 72 years (range 35-93). Mean Charlson co-morbidity index was 4.3. Mean follow-up was 3.2 years (range 1.3-5.7). Staphylococcal species were isolated in 11 cases (44%) (MRSA 1, MSSA 5, Staph. epidermidis 4 and Staph Pasteuri 1). Other bacteria included E. Coli (2), Streptococci spp. (3), Propionebacterium acnes (1) and Pseudomonas aeruginosa (1). Four cases were polymicrobial infection (16%), and no organisms were identified in two cases (8%). Candida albicans was identified in one case. All cases of bacterial infection were treated with prolonged oral doxycycline or amoxicillin. Twenty patients (80%) received 6 weeks of intravenous antibiotics prior to commencing prolonged oral antibiotics. Two patients experienced persistent symptoms and required amputation (both TKA). Two patients experienced sepsis but were treated successfully with IV antibiotics alone. The success rate of PSAT was 84% (21/25) successful at an average 3.2-year follow-up. DISCUSSION AND CONCLUSION: Prolonged suppressive antibiotic therapy is a viable option for the management of PJI with a low incidence of complications.

In-hospital outcomes following single-dose radiation therapy in the treatment of heterotopic ossification of the hip following spinal cord injury-an analysis of 444 cases.

STUDY DESIGN: Retrospective chart review. OBJECTIVES: The objective of the study was to analyse the efficacy of single-dose radiation therapy in the treatment of heterotopic ossification (HO) following spinal cord injury (SCI). SETTING: Department of Spinal Cord Injury and Department of General and Trauma Surgery, BG-University Hospital Bergmannsheil Bochum, Ruhr-University Bochum, Germany. METHODS: Patients who were treated for HO around the hips following SCI at our institution between January 2003 and December 2013 were included in this retrospective cohort study. A total of 444 HO cases around the hip were treated with single-dose radiation therapy after a mean time interval of 4.9 days (0-97 days; s.d.=8.1) after HO diagnosis. Primary outcome measures were the number of HO relapses and the occurrence of adverse side effects related to the radiation therapy. RESULTS: After a mean time interval of 63.2 days (8-295 days; s.d.=39.6) subsequent to SCI HO occurred in 207 male (84.8%) and 37 female (15.2%) patients with a mean age of 46.4 years (18-81 years, s.d.=18.2). In 200 patients both hips were affected, whereas the remaining 44 HO occurred unilateral. None of the patients suffered primary side effects due to the radiation therapy. However, in 13 out of 244 patients (5.3%), HO relapse occurred. After repeated single-dose radiotherapy, one patient suffered joint ankylosis and therefore required surgical resection. CONCLUSION: Our results present that single-dose radiation therapy is a safe option in the treatment for spinal cord-injured patients suffering from HOs of the hips.

Ankylosing spondylitis does not increase the risk of neurogenic heterotopic ossification in patients with a spinal cord injury: a retrospective cohort study.

STUDY DESIGN: Retrospective chart review. OBJECTIVES: The present study was performed to analyze the impact of ankylosing spondylitis (AS) in developing heterotopic ossification (HO) in patients following spinal cord injury. SETTING: Department of Spinal Cord Injury and Department of General and Trauma Surgery, BG-University Hospital Bergmannsheil Bochum, Ruhr-University Bochum, Germany. MATERIALS AND METHODS: Between January 2003 and December 2015, 67 patients with AS and SCI were included in the study. The control group consisted of 141 patients with SCI and without AS. The definitive diagnosis of HO was made via magnetic resonance imaging or computed tomography. Primary outcome measure was to analyze the impact of AS on the development of HO. RESULTS: Fifteen out of 67 AS patients (22.4%) had a diagnosed HO. In the control group, 28 of 141 patients (19.9%) suffered from HO. Patients with AS had no significant higher risk for HO development compared with patients without AS (RR=1.16; 95% CI=0.65-2.09). However, patients with a complete neurological deficit had a twofold higher risk for HO development (RR=2.55; 95% CI=1.26-5.16). CONCLUSIONS: AS does not increase the risk for HO development in patients with spinal cord injury.

The sensitivity of ultrasound screening examination in detecting heterotopic ossification following spinal cord injury.

STUDY DESIGN: Retrospective chart review. OBJECTIVE: To analyze the role of sonography in detecting heterotopic ossification (HO) following spinal cord injury (SCI). SETTING: Department of Spinal Cord Injury and Department of General and Trauma Surgery, BG University Hospital Bergmannsheil Bochum, Ruhr University Bochum, Germany. METHODS: Between January 2003 and December 2013, 217 patients with HO of the hips met the inclusion criteria and were included in the final analyses. The diagnosis of HO was carried out in all cases using our hospital protocol. Primary outcome measure was to calculate the sensitivity of ultrasound screening examination in detecting HO following SCI. RESULTS: The diagnosis of HO was confirmed in 217 patients after a mean interval of 64.8 days (range from 8 to 295; s.d.=40.4) via computerized tomography or magnetic resonance imaging scan. In 193 out of 217 patients, suspicious HO signs were noted in the ultrasound screening examination (sensitivity=88.9%). CONCLUSIONS: The use of ultrasound for screening for HO in SCI patients is reliable and has a high sensitivity.

Heterotopic ossification of the shoulder joint following spinal cord injury: an analysis of 21 cases after single-dose radiation therapy.

STUDY DESIGN: Retrospective chart review. OBJECTIVES: Heterotopic ossification (HO) affecting the hips is a common complaint of patients suffering traumatic spinal cord injury. However, the incidence of HO of the shoulder is considerably rare. In this context, we report on our results of 13 patients with a total of 21 cases of shoulder HO and single-dose radiation therapy. SETTING: Department of Spinal Cord Injury and Department of General and Trauma Surgery, BG-University Hospital Bergmannsheil Bochum, Ruhr-University Bochum, Germany. METHODS: The study group consists of 12 male and 1 female patient with a mean age of 55.5 years (range from 24 to 81 years; s.d.=14.5). Primary outcome measures were defined as the number of HO relapses and the number of side or adverse effects in relation to the radiation therapy. RESULTS: At the time of latest follow-up during hospitalization, the mean shoulder flexion was 92.1° while mean abduction was 94.5°. The average external rotation was 26.4°. No HO recurrence occurred and none of the patients suffered any adverse effects related to radiation therapy. CONCLUSIONS: In conclusion, single-dose radiation therapy in the treatment of shoulder HO due to spinal cord injury is an effective and reliable method, although the risk of secondary side effects related to the radiation therapy remain unknown.

The roles of serum alkaline and bone alkaline phosphatase levels in predicting heterotopic ossification following spinal cord injury.

STUDY DESIGN: Retrospective chart review. OBJECTIVES: To analyze the usefulness of serum alkaline phosphatase (AP) and bone alkaline phosphatase (BAP), as well as C-reactive protein (CRP) levels in predicting heterotopic ossification (HO). SETTING: Department of Spinal Cord Injury and Department of General and Trauma Surgery, BG-University Hospital Bergmannsheil, Ruhr University Bochum, Germany. METHODS: Between January 2003 and December 2013, 87 patients with HO around the hips met the inclusion criteria and were included in the study. Alkaline phosphatase, CRP and BAP were assessed and interpreted at the time of HO diagnosis and after radiation therapy in all patients. RESULTS: At the time of HO diagnosis, 49 out of 87 patients (49.4%) had elevated alkaline phosphatase levels and 39 out of 87 patients (44.8%) had elevated BAP levels. Elevated CRP values were found in 67 patients (77.0%). Within 3 days after single-dose radiation therapy, elevated AP levels persisted in 38 patients (43.7%) and elevated BAP levels in 28 patients (32.2%). CONCLUSIONS: The results obtained show that the determination of CRP, AP and BAP levels may not be considered a reliable screening method for early HO detection, subsequent to spinal cord injury.

[Exoskeletons for rehabilitation of patients with spinal cord injuries. Options and limitations]. / Exoskelette in der Rehabilitation Querschnittgelähmter. Möglichkeiten und Grenzen.

BACKGROUND: Mobile exoskeletons are increasingly being applied in the course of rehabilitation and provision of medical aids to patients with spinal cord injuries. OBJECTIVES AND METHODS: This article gives a description of the currently available exoskeletal systems and the clinical application including scientific and medical evidence, to derive recommendations regarding clinical practice of the various exoskeletons in the rehabilitation of patients with spinal cord injuries. RESULTS: The different systems represent a useful adjunct to the therapeutic regimen depending on the medical objectives. Posture-controlled exoskeletons in particular enable mobilization of patients with neurological gait disorders via direct motion support. In addition the neurologically controlled exoskeleton HAL® leads to functional improvements in patients with residual muscular functions in the chronic phase of spinal cord injury in terms of improved walking abilities subsequent to training. However, beneficial effects on bone density, bladder function and perfusion are conceivable but not yet adequately supported by evidence. Positive effects on spasticity and neuropathic pain are currently based only on case series or small clinical trials. CONCLUSION: Although exoskeletons are not yet an established tool in the treatment of spinal cord injuries, the systems will play a more important role in rehabilitation of patients with spinal cord injuries in the future. Neurologically controlled exoskeletons show beneficial effects in the treatment of acute and chronic spinal cord injuries and might therefore evolve to be a useful alternative to conventional locomotion training.

[Development of compartment syndrome after intravenous administration of an X-ray contrast medium. Recommendations on acute therapy regimens]. / Kompartmentsyndrom nach paravasaler Applikation von Röntgenkontrastmittel. Empfehlung zum akuten Therapieregime.

The incidence of extravasation of contrast medium is reported in the literature to be between 0.2 % and 0.9 %. A rare consequence of this could be compartment syndrome of the affected limb which requires immediate treatment.We report the case of a patient who developed acute compartment syndrome of the forearm after intravenous injection of radiographic contrast medium in a radiovolar vein during a computed tomography (CT) scan for multiple trauma. The clinical symptoms with pain, loss of range of motion and sensitivity functions, measurement of compartment pressure and radiological images confirmed the diagnosis. After emergency dermatofasciotomy of the forearm the full range of motion and sensitivity functions could be restored.

Does spinal cord injury influence the mortality rate in patients with necrotizing fasciitis?

STUDY DESIGN: Retrospective chart review. OBJECTIVES: This study was performed to compare the outcome, especially the mortality rate, in patients with and without spinal cord injury (SCI) and necrotizing fasciitis (NF). SETTING: Division of Spinal Cord Injury and Department of Plastic and Hand Surgery, BG-University Hospital Bergmannsheil Bochum, Ruhr-University Bochum, Germany. METHODS: Twenty-five patients with SCI and thirty patients without SCI treated with NF were included in the study. Mean length of hospital stay, mean age, mean laboratory risk indicator for necrotizing fasciitis (LRINEC) score, mean number of surgical debridements, co-morbidity factors and mortality rate were compared between both groups. RESULTS: There were no differences for the mean LRINEC score (P=0.07), mean number of surgical debridements (P=0.18) and co-morbidities (odds ratio=2.32; 95% confidence interval =0.78-6.92) between both groups. Patients with SCI were significantly younger than patients without SCI (P=0.02). Patients without SCI had a higher mortality risk rate (n=9) than patients with SCI (n=2) (relative risk=1.71; 95% confidence interval =1.13-2.6). CONCLUSIONS: In conclusion, SCI patients have a lower mortality rate than patients without SCI. Age may influence the mortality rate. Nevertheless, we believe that further unknown risk factors might influence the mortality, especially in patients with SCI.

[Handling modern imaging procedures in a high-tech operating room]. / Handling moderner Bildgebung in einem Hightech-Operationssaal.

Operating rooms are the central unit in the hospital network in trauma centers. In this area, high costs but also high revenues are generated. Modern operating theater concepts as an integrated model have been offered by different companies since the early 2000s. Our hypothesis is that integrative concepts for operating rooms, in addition to improved operating room ergonomics, have the potential for measurable time and cost savings. In our clinic, an integrated operating room concept (I-Suite, Stryker, Duisburg) was implemented after analysis of the problems. In addition to the ceiling-mounted arrangement, the system includes an endoscopy unit, a navigation system, and a voice control system. In the first 6 months (9/2005 to 2/2006), 112 procedures were performed in the integrated operating room: 34 total knee arthroplasties, 12 endoscopic spine surgeries, and 66 inpatient arthroscopic procedures (28 shoulder and 38 knee reconstructions). The analysis showed a daily saving of 22-45 min, corresponding to 15-30% of the daily changeover times, calculated to account for potential savings in the internal cost allocation of 225-450 EUR. A commercial operating room concept was evaluated in a pilot phase in terms of hard data, including time and cost factors. Besides the described effects further savings might be achieved through the effective use of voice control and the benefit of the sterile handle on the navigation camera, since waiting times for an additional nurse are minimized. The time of the procedure of intraoperative imaging is also reduced due to the ceiling-mounted concept, as the C-arm can be moved freely in the operating theater without hindering cables. By these measures and ensuing improved efficiency, the initial high costs for the implementation of the system may be cushioned over time.

[A new reduction technique for posterior locked shoulder dislocation. Case report and technique description]. / Eine neue Repositionstechnik für die verhakte hintere Schulterluxation. Fallbericht und Beschreibung der Repositionstechnik.

The case of a 61-year-old male with posterior dislocation of the right shoulder joint is presented and a new technique for closed reduction of posterior locked shoulder dislocation is described. The technique involves four steps: in step 1 a constant traction is applied on the injured arm, in step 2 the arm is internally rotated and in steps 3 and 4 the second arm of the physician is used as a lever arm to lateralize and ventralize the shoulder. Lateralization and ventralization of the humeral head are essential to engage the humeral head and to pass it around the glenoid during reduction. Steps 3 and 4 are performed simultaneously. In the presented case the patient suffered a traumatic shoulder dislocation with a rim fracture of the glenoid. After reduction the shoulder was stable and conservative treatment was performed. A 2 year follow-up examination revealed a pain-free and stable shoulder with free range of motion and an Oxford instability score of 48 points. The described reduction technique for posterior locked shoulder dislocation is a simple and gentle technique, which can be performed easily by one person.Presentation of a reduction technique for locked posterior shoulder dislocation. Constant traction and internal rotation is performed for engaging the locked humeral head. After disengaging the humeral head the reduction is performed by using the arm of the physician as a lever arm.

Acetabular Reconstruction Using Multiple Porous Tantalum Augments: Three-Quarter Football Augment.

Reconstruction of a large acetabular bone defect is a complex problem in revision hip arthroplasty. The authors report a novel method of reconstructing an uncontained acetabular defect (Paprosky type IIIb) using multiple tantalum augments. A 73-year-old female patient presented to our institution with a chronically dislocated primary left total hip arthroplasty with radiographs demonstrating migration of acetabular component and formation of pseudoarthrosis within the left ilium. Extensive arthrolysis and anatomic reconstruction of the acetabular bone defect were performed using the novel method of multiple tantalum augments. Postoperatively, recovery was initially complicated by multiple dislocations requiring an exchange to an elevated liner, however subsequently achieved good function.

Pressure sores significantly increase the risk of developing a Fournier's gangrene in patients with spinal cord injury.

STUDY DESIGN: Retrospective chart review. OBJECTIVES: The aim of our study was to evaluate the mortality rate and further specific risk factors for Fournier's gangrene in patients with spinal cord injury (SCI). SETTING: Division of Spinal Cord Injury, BG-University Hospital Bergmannsheil Bochum, Ruhr-University Bochum, Germany. METHODS: All patients with a SCI and a Fournier's gangrene treated in our hospital were enrolled in this study. Following parameters were taken form patients medical records: age, type of SCI, cause of Fournier's gangrene, number of surgical debridements, length of hospital and intensive care unit stay, co morbidity factors and mortality rate. In addition, laboratory parameter including the laboratory risk indicator for necrotizing fasciitis (LRINEC) score and microbiological findings were analyzed. Clinical diagnosis was made via histological examination. RESULTS: A total of 16 male patients (15 paraplegic and one tetraplegic) were included in the study. In 81% of all cases, the origin of Fournier's gangrene was a pressure sore. The median LRINEC score on admission was 6.5. In the vast majority of cases, a polybacterial infection was found. No patient died during the hospital stay. The mean number of surgical debridements before soft tissue closure was 1.9 and after a mean time interval of 39.1 days wound closure was performed in all patients. CONCLUSIONS: Pressure sores significantly increase the risk of developing Fournier's gangrene in patients with SCI. We reported the results of our patients to increase awareness among physicians and training staff working with patients with a SCI in order to expedite the diagnosis.

[Spine fractures in patients with ankylosing spondylitis: an analysis of 129 fractures after surgical treatment]. / Wirbelsäulenfraktur bei ankylosierender Spondylitis : Eine Analyse von 129 Frakturen nach operativer Versorgung.

INTRODUCTION: The ankylosing spondylitis (AS) is a systemic rheumatic disease, which affects the skeleton, joints and internal organs. Attributed to the augmented rigidity of the spine and the concomitant impairment of compensatory mechanism minor force might cause spine fractures. Multilevel stabilization and dorsoventral instrumentation is a well - established procedure. This study was to evaluate the surgical outcome of 119 patients with AS associated spine fractures. METHODS: From 07/96 to 01/10, 119 patients with 129 spine fractures due to AS were treated in our department. Data were collected retrospectively. In all patients the operative treatment of the fracture was either performed by ventral and/or dorsal spondylodesis. RESULTS: The median age was 67 years (37-95). There were 51 cervical, 55 thoracic and 23 lumbar spine fractures. On initial presentation no fractures in 18 patients (15%) and stable fractures in 15 patients (13%) were detected, which further secondarily dislocated. Thus, in 28% of the patients the injury was assessed falsely. 47% of the fractures were preceded by a trivial trauma in domestic surrounding. 61 patients (51%) developed either an incomplete or a complete paraplegia. In 32 patients ventral instrumentation, in 82 patients dorsal and in 15 patients dorsoventral instrumentation were performed. 14% developed postoperative wound infection an in 15% revision surgery due to implant loosening or insufficient stabilization was required. CONCLUSION: Early diagnostic of AS associated spine fractures using conventional radiographs and computed tomography scans is important for the detection and adequate treatment. A great amount of spine fractures are obviously either under diagnosed or underestimated, initially. A secondary dislocation of the fracture might result in severe neurological complications up to paraplegia.

Sigmoido-gluteal fistula--a rare complication in clinically asymptomatic chronic diverticulitis.

Chronic colonic diverticulitis may be associated with typical complications such as local abscesses, stenosis, bleeding, intraperitoneal bowel perforations or fistulas to other organs. Most commonly, fistulas exist between the colon and the bladder; nevertheless, they may also extend to the small intestine, other areas of the colon, ureter, uterus, salpinx, vagina, abdominal wall, portal- and mesenterial venous system, pleura, urachus, biliary system and the hip. We report on a patient with chronic colonic diverticulitis having an unusual sigmoido-gluteal fistula along the sacrum, the piriformis muscle and sciatic nerve. The patient presented with sciatic nerve symptoms and recurrent gluteal abscess formation, but no other clinical symptoms leading to an abdominal pathology. Initially, that fact caused an unsuccessful local treatment under the differential diagnosis of a local gluteal abscess for about a year. Finally, a sigmoid colon resection with end-to-end anastomosis and a proximal diverting stoma was performed. The colostomy was closed electively five months later without any complication.

[Salvage procedures of the elbow. Alternatives to elbow arthroplasty]. / Salvage procedures am ellenbogen. Alternativen zur ellenbogenendoprothetik.

Destructive changes of the elbow joint represent a challenge for both patient and surgeon. Resection arthroplasty is associated with postoperative instability and loss of power and is a rarely performed procedure. Interpositional arthroplasty remains a useful option for healthy active patients with severe post-traumatic elbow arthrosis and is one of the oldest methods used to reconstruct the elbow. The principle of interpositional arthroplasty is based on a sparing resection of the destroyed joint surface and on creating a congruent elbow joint with human tissue. Nowadays, autogenous dermis, fascia lata or Achilles allograft are used. A preoperatively stable elbow is required to prevent instability following interpositional arthroplasty. The use of total elbow arthroplasty is limited due to the contraindications and in such cases the only remaining options are salvage procedures of the elbow. In general, arthrodesis should be performed in patients with painful osteoarthritis of the elbow with high demands on the upper extremities. Historically, tuberculosis was the most common indication for elbow arthrodesis and various methods of elbow arthrodesis have been described. However, most attention has been given to the position in which the elbow joint should be fixed and should be decided depending on the individual characteristics of the patient. Sufficient bone stock is crucial for a successful elbow arthrodesis and in cases with massive bone loss reconstruction of the elbow using an allograft can be performed to restore bone quality. However, the high complication rate of this procedure limits the scope of its use. Nevertheless, allograft procedures can restore pain-free joint function for several years.

Computer-assisted antetorsion control prevents malrotation in femoral nailing: an experimental study and preliminary clinical case series.

MATERIALS AND METHODS: The effect of fluoroscopy-based navigation for femoral fracture reduction on the prevention of malrotation was examined in an experimental setting followed by a first case series. Eleven cadaver femurs were used. All femurs were reduced by closed methods. An optoelectronic navigation system was utilized to check for fragment reduction and alignment. Fluoroscopic control without navigation was used as the control group. The Six Sigma Analysis [offset capability index (C (pk)) = 1.3] was used to compare the probability of outliers of more than 15 degrees . In the clinical case series the same navigation tool was used in ten non-consecutive patients with femoral fractures. Torsional differences between both legs were measured postoperatively by CT scan. RESULTS: The highest malrotation in the navigated group was 7.0 degrees for the cadaver testings, while two femurs in the control group showed a difference of more than 10 degrees (10.3 degrees , 17.4 degrees). Only the navigated group showed a sufficient offset capability index (C (pk-navigated) = 1.83; C (pk-conventional) = 0.59). In the clinical series nine femurs were successfully reduced by navigation control. The average malrotation was 6.6 degrees . No patient had a torsional difference of more than 10 degrees. CONCLUSION: Navigated femoral nailing reduces the risk for outliers of postoperative torsional differences and might avoid revision surgery for malrotation. LEVEL OF EVIDENCE: IV.

Heterotopic Ossification in Orthopaedic and Trauma surgery: A Histopathological Ossification Score.

Heterotopic Ossification (HO) is a potential long-term complication in orthopaedic surgery. It is commonly classified according to the Brooker classification, which is based on radiological findings. To our knowledge the correlation of histological features to the Brooker grade is unknown as is the association between HO and the indication for revision. The aim of this paper is to analyze the ossification grade of HO tissue in patients undergoing revision hip and knee arthroplasty and to propose a histologically based classification system for HO. We also assess the relationship between the grade of HO and the indication for revision (septic and aseptic revision). From January to May 2019 we collected 50 human HO samples from hip and knee revision arthroplasty cases. These tissue samples were double-blinded and sent for histopathological diagnostic. Based on these results, we developed a classification system for the progression of HO. The grade of ossification was based on three characteristics: Grade of heterotopic ossification (Grade 1-3), presence of necrosis (N0 or N1) and the presence of osteomyelitis (HOES-Score Type 1 to 5). Demographic data as well as surgical details and indication for surgery was prospectively collected from clinical records. Fifty tissue samples were harvested from 44 hips and 6 knee joints. Of these 33 exhibited Grade I ossifications (66%), followed by 11 Grade II (22%) and one Grade III (2%). Necrosis was noted in two tissue samples (4%) and 2 more had osteomyelitis findings according to HOES-Score. Six samples (12%) with radiologically suggestive of HO turned out to be wear-induced synovitis, SLIM Type 1. Of these cases 16 were septic (32%) and 34 aseptic (68%) revisions. Most of the HO tissue samples were classified as a low-grade. High-grade ossification-Score is rare. Higher grades of ossification seem to be associated with septic revision cases. Wear-induced synovitis potentially influences HO development. A histological scoring system for ossification grading can be derived from the data presented in this study.

Percutaneous bone biopsy. A new application for 3D navigation: a pilot study.

Computer Tomography (CT) guided percutaneous bone biopsy has been established as a minimally invasive method for the rapidly obtaining samples from osseous lesions for histological examination. With this method, an overall accuracy of 90% can be obtained without a significant radiation exposure. The aim of this study was to develop a navigated sleeve for the Jamshidi needle in order to perform navigated, percutaneous bone biopsies with the help of Iso-C-3D. Utilizing this navigated biopsy needle, the procedure was analyzed for several parameters including precision, total operating time, and level of radiation exposure. By using the Iso-C-3D navigation the total operating time was 11.7 min (8-14.3) and radiation exposure was 1.6 (0.67-2.12 min). This study demonstrates that navigated percutaneous bone biopsies can be obtained fast and with low radiation exposure. The feasibility of Iso-C-3D navigated bone biopsies is tempered by the requirement a rigidly fixed dynamic reference frame.