[Case report of an osseous (and lymphogenic) thymic carcinoma in an adult]

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.

Resuming Elective Orthopaedic Surgery During the COVID-19 Pandemic: Guidelines Developed by the International Consensus Group (ICM)

»As we resume elective surgical procedures, it is important to understand what practices and protocols should be altered or implemented in order to minimize the risk of pathogen transfer during the severe acute respiratory syndrome (SARS)-CoV-2 pandemic. »Each hospital and health system should consider their unique situation in terms of SARS-CoV-2 prevalence, staffing capabilities, personal protection equipment supply, and so on when determining how and when to implement these recommendations. »All patients should be screened for SARS-CoV-2 by means of a thorough history and physical examination, as well as reverse transcription-polymerase chain reaction (RT-PCR) testing whenever possible, prior to undergoing elective surgery. »Patients who are currently infected with coronavirus disease 2019 (COVID-19) should not undergo elective surgery. »These guidelines are based on the available scientific evidence, albeit scant. The recommendations have been reviewed and voted on by the expert delegates who produced this document.

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.

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.

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.

Septic single-stage knee arthrodesis after failed total knee arthroplasty using a cemented coupled nail

Knee arthrodesis is a potential salvage procedure for limb preservation after failure of total knee arthroplasty (TKA) due to infection. In this study, we evaluated the outcome of single-stage knee arthrodesis using an intramedullary cemented coupled nail without bone-on-bone fusion after failed and infected TKA with extensor mechanism deficiency. Between 2002 and 2012, 27 patients (ten female, 17 male; mean age 68.8 years; 52 to 87) were treated with septic single-stage exchange. Mean follow-up duration was 67.1months (24 to 143, n = 27) (minimum follow-up 24 months) and for patients with a minimum follow-up of five years 104.9 (65 to 143,; n = 13). A subjective patient evaluation (Short Form (SF)-36) was obtained, in addition to the Visual Analogue Scale (VAS). The mean VAS score was 1.44 (SD 1.48). At final follow-up, four patients had recurrent infections after arthrodesis (14.8%). Of these, three patients were treated with a one-stage arthrodesis nail exchange; one of the three patients had an aseptic loosening with a third single-stage exchange, and one patient underwent knee amputation for uncontrolled sepsis at 108 months. All patients, including the amputee, indicated that they would choose arthrodesis again. Data indicate that a single-stage knee arthrodesis offers an acceptable salvage procedure after failed and infected TKA.

Infection rates in patients undergoing primary knee arthroplasty with pre-existing orthopaedic fixation-devices

BACKGROUND

Prior knee surgery in the setting of knee arthroplasty (KA) can influence the overall outcome of the procedure and render the operation more technically challenging. The effects of residual fixation devices on subsequent procedures about the knee are ill-defined. Some authors claim an increase in periprosthetic infection in this cohort of patients. The objective of this study was to evaluate the overall incidence of periprosthetic infections in patients undergoing primary KA with pre-existing osteosynthetic hardware in situ.

METHODS

The current investigators retrospectively reviewed 124 patients undergoing knee arthroplasty and removal of orthopaedic fixation devices, due to prior high tibial osteotomies, fracture fixation or cruciate ligament reconstruction. The exclusion criterion was a prior history of infection of the fixation device. The mean follow-up time was 5.4 years (range 15 months to 9 years). Nine patients were lost to follow-up.

RESULTS

Joint aspiration was performed two weeks prior to surgery in 53 patients (42.4%) and intra-operative samples were obtained in 106 patients (84.8%), which did not show any bacterial growth. A subacute periprosthetic infection occurred after seven months in only one patient.

CONCLUSION

The results of the current study demonstrate that previously implanted osteosynthetic fixation devices do not significantly increase the risk of developing periprosthetic knee infections. A two-stage procedure with implant retrieval prior to total knee arthroplasty is not clinically indicated in the cohort described, amongst whom an infection rate of 0.9% was revealed.

[Non-traumatic anterior knee dislocation in a patient with osteoarthritis of the knee]

Complete knee dislocation is a rare and severe injury and usually follows high-energy trauma. Non-traumatic knee dislocations are exceedingly rare, while severe overweight appears to be the main cause of the knee dislocation. We here report on a spontaneous knee dislocation in a patient with severe osteoarthritis of the left knee. A 68-year-old woman was admitted to our hospital for an elective total knee replacement. One year prior to admission, a planned joint replacement was not performed due to an existing ulcus cruris. After healing of the ulcus cruris, the patient presented with progressive pain and instability of the left knee without any trauma. The clinical examination showed a multidirectional instability of the left knee with a restricted range of motion (ROM) with 0-0-40 degrees for extension and flexion. The performed radiological examination revealed an anterior knee dislocation of the left knee. Intraoperative findings suggest a non-traumatic aetiology. We suspect that osteoarthritis of the left knee has caused the dislocation. Therefore, we recommend, even in usually "harmless" osteoarthritis, close clinical and radiological follow-up examinations to detect and treat possible complications.

[A new reduction technique for posterior locked shoulder dislocation. Case report and technique description]

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.

[The pressure-sensitive swelling in the knee as a sign for a monoclonal gammopathy of undetermined specificity (MGUS)]

AL amyloidosis (AL-A) is seen in about 6-15 % of patients with multiple myeloma. In contrast, the sporadic occurrence of AL-A is a rarity. The presence of amyloid is often found in the respiratory tract followed by the lung, the eyelids, the skin and the lower urinary tract, while the presence in soft tissues or bone is rather uncommon. We here describe a 71-year-old woman who presented with a pressure-sensitive swelling in the left knee at our hospital. The clinical examination on admission showed a tumourous alteration of the popliteal soft tissues without any signs of neurological deficits. However, the range of motion (ROM) of the left knee was restricted with 0-0-100 degrees for extension and flexion. A dialysis-dependent renal insufficiency, heart insufficiency with the necessity of permanent anticoagulation and glaucoma were noted as pre-existing illnesses. Further diagnostic examinations including ultrasound and magnetic resonance imaging (MRI) of the left knee revealed a solid tumourous structure with a radiological suspicion of pigmented villonodular synovitis. A complete surgical extirpation of the tumourous structure was performed. The further performed diagnostic examinations including histological and immunohistochemical analyses showed evidence of an AL-A tumour. A monocloncal gammopathy of unknown specificity (MGUS) was detected as an origin for the AL-A. This case underscores the necessity of complete extirpation and histological and immunohistochemical analyses of any soft tissue tumour. Possible previously existing rare malignant diseases can be detected only in this way.

Characteristics and differences in necrotizing fasciitis and gas forming myonecrosis: a series of 36 patients

BACKGROUND AND AIMS

Necrotizing fasciitis (NF) and gas forming myonecrosis (GFM), both being subtypes of necrotizing soft tissue infection (NSTI), are life threatening conditions sharing certain similarities. Despite the necessity of early and radical surgical debridement in necrotizing infections, the distinction between these entities is of clinical relevance since gas forming myonecrosis in a number of cases results from an underlying abdominal cause and the focus of infection can be missed. This study was to evaluate the incidence and risk factors as well as the mortality rate in patients with NSTI and GFM.

MATERIAL AND METHODS

All patients with NSTI treated in the authors' hospital between January 2005 and Decem-ber 2009 were enrolled in the study. Medical records, histological slides, microbiological and laboratory parameters as well as Computerized Tomography (CT) and magnetic resonance imaging (MRI) scans were reviewed for all patients. Differences between NF and GFM regarding hospital stay, number of surgical interventions and pre-existing comorbidities as well as mortality rate were analyzed. The laboratory risk factor for necrotizing fasciitis (LRINEC) score was calculated in all patients on admission.

RESULTS AND CONCLUSIONS

Thirty patients (17 female, 13 male) with necrotizing fasciitis with a mean age of 55 years (SD 15.5) were included in the study. There was no statistically significant difference between survivors and deceased patients comparing the LRINEC score (n.s.). Patients with necrotizing fasciitis secondarily involving the trunk had a significantly higher mortality rate (OR 11.2; 95% CI=1.7-72.3). In the majority of cases (12 cases), minor skin lesions were identified as the site of origin. Amongst all necrotizing soft tissue infections six patients (female n=3; male n=3) with a mean age of 61.5 years (SD 12.2) with non-clostridial gas forming myonecrosis were identified. Three patients had a history of malignancy and in three patients the infection was secondary to major surgery. The mean LRINEC score was 8.5 (SD 1). Three patients (50%) died due to GFM. Early diagnosis and appropriate intervention is critical to provide accurate treatment decisions. Eradicating the differing primary sources of infection in GFM and NF will have a positive impact on outcome.

[Handling modern imaging procedures in a high-tech operating room]

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.

[Spine fractures in patients with ankylosing spondylitis: an analysis of 129 fractures after surgical treatment]

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.

[Underdiagnosed disco-ligamentous lesion in the cervical spine of a paraglider]

INTRODUCTION

Paragliding is an increasingly popular airborne sport with numerous associated injuries. We here describe the case of an experienced paraglider who, after a fall from 15 meters, presented with an initially underdiagnosed disco-ligamentous lesion of the cervical spine.

PATIENT AND METHOD

We report on a 51-year-old male paraglider, who was referred to our hospital four days after a fall from 15 meters. Initial treatment was performed in a regional hospital. The performed clinical and radiological examinations including computerized tomography showed, besides a fracture of the radius, no further abnormalities.

RESULTS

The patient was discharged home four days after injury. Due to persistent pain in the cervical spine and parasthesia, the patient was referred to the practicing orthopaedic surgeon. The performed MRI and CT including the sagittal and coronal planes showed a disco-ligamentous lesion of the cervical spine. The patient was transferred immediately to our hospital for surgical treatment. The initial existing neurological symptoms resolved postoperatively and the patient was discharged home in a well condition.

DISCUSSION

Injuries of the cervical are extremely rare in paragliders. Nevertheless, this case underscores the importance of adequate clinical and radiological examinations. We report the case of our patient to increase awareness among physicians and training staff working in emergency rooms.

Clinical outcome and complications using a polyaxial locking plate in the treatment of displaced proximal humerus fractures. A reliable system?

INTRODUCTION

The surgical treatment of displaced proximal humeral fractures (ORIF) is a perpetual challenge to the surgeon. For this reason, the principle of polyaxiality was developed to provide an improved primary stability of the fracture through better anchorage of the screws, especially in osteoporotic bone. The aim of this study was to present clinical results with the polyaxial locking plate in the operative treatment of proximal humerus fractures in order to determine whether the technique of polyaxiality leads to better functional outcome and lower complication rates in comparison to monoaxial plates in the literature.

PATIENTS AND METHODS

Seventy-three patients with displaced proximal humeral fractures were treated surgically with the polyaxial locking Suture Plate™ (Arthrex(®)) between 03/2007 and 06/2009. Fifty-two of the patients (mean age, 69.9 ± 12.1) were included in a radiographical and clinical examination using the Constant score (CS) and the Disabilities of the Arm, Shoulder and Hand score (DASH).

RESULTS

The follow-up examinations were on average 13.9 ± 4.5 months (10-27 months) after surgical treatment. The mean CS of the patients was 66.0 ± 13.7 points, the age- and gender-related CS was 90.9% ± 20.0% and the mean DASH score was 23.8 ± 19.8 points for the injured side. The patients with a nearly anatomical reduction of their fracture (n = 13) reached a significantly higher CS (75.1 ± 8.5; p = 0.004) and DASH-score (13.6 ± 11.6; p = 0.043) and none of these patients had a complication. The complications were identified in 12 (23.1%) cases, 5 of which involved loss of reduction. All of these 5 cases were lacking of initial medial column support and 4 of which were type C2.3 AO-Classification.

CONCLUSION

The data show that the combination of angular stability with the possibility of variable polyaxial screw direction is a good concept for reduction and fixation of displaced proximal humeral fractures, but anatomical reduction and medial support remain important preconditions for a good outcome. However, a significantly lower rate of complications or better clinical outcome than that reported in the literature could not be found.

[Outpatient treatment of metacarpal and phalangeal fractures leads to similar outcomes compared to inpatient treatment]

Metacarpal and phalangeal fracture fixation may be conducted in ambulatory or inpatient settings. However, to date, little is known about the outcomes of the surgical treatment of metacarpal and phalangeal fractures in the two population groups. The aim of this study was to compare the surgical outcomes of patients undergoing treatment for metacarpal and phalangeal fractures in the ambulatory setting as compared to those in in-hospital settings. All patients who were surgically treated for metacarpal and phalangeal fractures at our institution were enrolled in this study. All patients treated non-surgically, as well as those who had sustained open fractures, were excluded from the study. A total of 85 patients met our inclusion criteria. Based on the length of hospital stay, patients were divided into two groups: inpatient (> 24 hours) and outpatient (< 24 hours). Fifty-three out of the eighty-five patients were available for follow-up examination. Patients were re-evaluated at a mean 17.9 months (range: 4-48 months; SD = 10 months) after surgery. Physical function in everyday life and specific hand function were compared between the groups using the DASH and Cooney outcome questionnaires. Range of motion of the affected side was measured using a standard goniometer and was evaluated as a proportion of total active motion (% TAM) relative to the contralateral uninjured side. Complication rates were calculated and compared between groups. There were no differences for the DASH outcome scores for phalangeal and metacarpal fractures on comparing both groups. There was also no statistically significant difference for the mean Cooney score for phalangeal fractures in both groups. The inpatient group had a significantly higher mean Cooney score (mean: 93.5; range, 70-100; SD 8.8; 95 % CI = 87.2, 99.8) after metacarpal fracture fixation than the outpatient group (mean: 82.5; range: 55-100; SD 14.5; 95 % CI = 75.3, 89.7) (p = 0.01). There was no statistically significant difference on comparing the mean proportion of total active motion (% TAM) relative to the contralateral uninjured side between the inpatient and outpatient groups (p > 0.05). The overall complication rate was 20.7 % (n = 11). The most common complication was postoperative infection with six cases (three inpatients; three outpatients). Outpatient surgical treatment of metacarpal and phalangeal fractures results in similar outcomes compared to inpatient treatment. Outpatient treatment of metacarpal and phalangeal fractures should be considered whenever possible.

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.

[Two-stage traumatic rupture of the arteria ovarica after high energy trauma]

INTRODUCTION

Rupture of the Arteria ovarica is a rare but life-threatening injury and occurs primarily in pregnancy. Most previously described ruptures of the Arteria ovarica were in the early postpartum period and in women who were older than 45 years. We report on a two-stage rupture of the Arteria ovarica after a high energy trauma, which has not previously been described in the literature.

PATIENT AND METHOD

A 66-year-old female patient was admitted to the emergency room after a car accident. Initial treatment was performed in a regional hospital. Initial clinical and radiological examinations were without any pathologies and the patient was discharged home after ambulatory treatment. Six days later, the patient was referred to our hospital because of increasing headache. A computed tomography of the head showed a subdural haematoma. A follow-up CT scan after three days showed no further progression of the haematoma.

RESULTS AND CONCLUSIONS

During the hospital stay, the patient developed abdominal pain, nausea and cardiovascular decompensation. An ultrasound of the abdomen showed free fluids, while a performed CT scan of the abdomen confirmed an arterial bleeding from a pseudoaneurysm of the left ovarian artery. An emergency operation was performed. Postoperative management included ICU monitoring, diuresis control and blood transfusion. The patient was discharged home after 19 days in a good condition. The indication for performing a CT scan and primary hospitalisation after a high energy trauma should be applied generously.

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.

[Paraplegia after isolated rupture of the spinal cord - a rare injury]

INTRODUCTION

Complex vertebral fractures can lead to injury of the spinal cord with resulting paraplegia. High-speed accidents are common causes, especially in younger patients. Malignant or inflammatory processes play an important role in the elderly. Less common reasons for a spinal cord injury are congenital malformations. We here report about a 17-year-old patient who suffered from paraplegia after an isolated rupture of the spinal cord without an injury of the vertebral bodies, intervertebral disc or ligamentous structures. This type of injury has not been reported in the literature before.

PATIENT AND METHOD

We report about a 17-year-old patient, referred to our hospital, presenting with lumbal paraplegia after a high-speed accident 8 days prior to admission. After initial stabilisation of the polytraumatised patient, he was referred to our hospital for further treatment.

RESULTS AND CONCLUSION

The radiological examination showed a bilateral acetabular fracture, a right anterior pelvic ring fracture and shaft fractures of the left humerus and right femur. Furthermore, the spinal cord at thoracic level 10/11 was ruptured. Interestingly, there was no injury of the vertebral bodies, intervertebral disc or ligamentous structures. A tethered cord as a possible anatomic variation could be excluded in this case by MRI. However, anatomic variations could be the reason for this injury and should be kept in mind.

[Arm wrestling injuries--report on 11 cases with different injuries]

INTRODUCTION

Arm wrestling may cause severe injuries. Various injuries after arm wrestling have been reported in the literature, whereas the most common injury is the humeral shaft fracture. In this context we report on eleven cases with different injuries during arm wrestling.

MATERIAL AND METHODS

All patients were analyzed using a standardized questionnaire. The effect of drugs, pre-existing conditions and injuries as well as sport activities were examined. Furthermore we report about a 24 year old patient who sustained a radial shaft fracture which has not been reported in the literature yet.

RESULTS

8 patients suffered from a fracture. The humerus was the most affected bone in 7 cases. 3 patients had a muscle strain, whereas in all 3 cases the patients were regularly sportive active and warmed-up be for the injury. Ten patients were reintegrated into the previous job after an average time period of 6 weeks. One patient was out of work.

CONCLUSIONS

Regular sport activity and the muscle strength are important factors for the injury intensity. Further studies are necessary to confirm this theory.

Radiolunate fusion in the rheumatoid wrist with Shapiro staples: clinical and radiological results of 22 cases

We performed a retrospective clinical and radiological case control study on 22 rheumatoid wrists following radiolunate fusion via Shapiro staples with a mean follow-up of 5 years. Radiographs showed one early loosening through dorsal staple migration and four nonunions. Six wrists fused in mild ulnopalmar dislocation of the lunate. Primary intra-articular positioning of a staple was found in nine wrists, secondary intra-articular staple dislocation was found in two wrists. Dorsal staple dislocation was found in four fused arthrodeses. Osteolysis around the staples was found in all but two wrists. In contrast to unsatisfactory radiological results the clinical results were good or excellent in 18 patients. Good and excellent clinical results in the majority of the patients following radiolunate fusion does not depend on the fixation device. Nevertheless staple fixation of the radiolunate joint in the rheumatoid wrist is associated with a high rate of radiological complications.

Implementation of a new navigated parallel drill guide for femoral neck fractures

Trauma navigation modules often use conventional mechanical surgical tools for basic simulation of drilling procedures or single screw placement. However, the precise parallel placement or specific angles that may be required are not displayed on the navigation screen. A more complex mechanical tool, a parallel drill guide (PDG) for femoral neck fractures, was integrated into a navigation module as part of this study, thus combining the advantages of mechanical tools with the benefits of fluoroscopic navigation. To implement a conventional PDG with a conventional navigation system, the tool was equipped with a non-detachable reflective marker array. Navigation engineers adapted the software to enable the navigated PDG to be displayed. We evaluated the conventional technique in comparison with the navigated technique using plastic bone models and a fresh frozen cadaver. Implementation of the navigated PDG did not pose any problems, in terms of either the software or the surgical procedure itself. The total operation time was extended by 30%, but the radiation time for the navigated group was reduced by 50%. No software or hardware-related failures occurred. Complete integration of a cannulated parallel drill guide into a navigation system has been successfully implemented. Continuous display of the mechanical guide with two parallel trajectories on the navigation screen enables safe, efficient screw placement within mechanical guidelines, without the need for additional radiographic control once initial registration has been completed.

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.

Accuracy of navigated surgery of the pelvis after surface matching with an a-mode ultrasound probe

Computer-aided surgery (CAS) allows for real-time intraoperative feedback resulting in increased accuracy, while reducing intraoperative radiation. CAS is especially useful for the treatment of certain pelvic ring fractures, which necessitate the precise placement of screws. Flouroscopy-based CAS modules have been developed for many orthopedic applications. The integration of the isocentric flouroscope even enables navigation using intraoperatively acquired three-dimensional (3D) data, though the scan volume and imaging quality are limited. Complicated and comprehensive pathologies in regions like the pelvis can necessitate a CT-based navigation system because of its larger field of view. To be accurate, the patient's anatomy must be registered and matched with the virtual object (CT data). The actual precision within the region of interest depends on the area of the bone where surface matching is performed. Conventional surface matching with a solid pointer requires extensive soft tissue dissection. This contradicts the primary purpose of CAS as a minimally invasive alternative to conventional surgical techniques. We therefore integrated an a-mode ultrasound pointer into the process of surface matching for pelvic surgery and compared it to the conventional method. Accuracy measurements were made in two pelvic models: a foam model submerged in water and one with attached porcine muscle tissue. Three different tissue depths were selected based on CT scans of 30 human pelves. The ultrasound pointer allowed for registration of virtually any point on the pelvis. This method of surface matching could be successfully integrated into CAS of the pelvis.

Value of 3D fluoroscopic imaging of acetabular fractures comparison to 2D fluoroscopy and CT imaging

PURPOSE

Intraoperative two-dimensional (2D) fluoroscopy of acetabular fractures is difficult due to the complex three-dimensional (3D) anatomy. Intraoperative 3D fluoroscopy may have particular utility in the evaluation of acetabular fractures. We compared the accuracy of 3D fluoroscopic imaging in evaluating acetabular fracture displacement and implant placement with fluoroscopy and computed tomography (CT) scans.

METHODS

In 24 cadaveric acetabuli, a transverse acetabular fracture was created. First a 2 mm step-off of the articular surface was created and reconstruction plates placed on the anterior and posterior columns. In 12 specimens, two screws were placed intraarticularly, protruded by 2 mm. In the remaining 12 specimens, the same constructs were used but the screws remained extraarticular. Second tests were designed to simulate an impaction injury. After hardware removal, a hollow trephine (diameter of 14.9 mm) was used to core a bone cylinder on the dome of the acetabulum, and impacted until it was recessed into the articular surface by 2 mm. Plates were placed, and screws were placed intraarticularly in 12 specimens, as in the first set of tests. All cadavers were imaged with standard 2D-, 3D fluoroscopy and CT. Three observers randomly evaluated all imaging studies for all specimens.

RESULTS

For detection of intraarticular screws, both the Iso-C3D and the CT scans were significantly more sensitive (96 and 96%, respectively) and specific (96 and 100%, respectively) in detecting the intraarticular position compared to 2D fluoroscopy (75%; P < 0.05). Sensitivity of articular step-off detection was no different between the Iso-C3D (83%), CT (79%), and 2D fluoroscopy (87%). Articular impaction was correctly identified in 79% of specimens with the Iso-C 3 D technique, while the CT was accurate in 92%. 2D fluoroscopy was accurate in 62% for the impactions (P < 0.05 vs. CT).

CONCLUSIONS

3D-fluoroscopic imaging appears to be extremely accurate in evaluating acetabular fracture constructs. Its sensitivity and specificity for evaluating intraoperative hardware was greater than with 2D fluoroscopy and equivalent to CT scan. Volumetric impactions were also reliably demonstrated on both of the 3D modalities, which were both superior to 2D fluoroscopy. Overall, Iso-C3D multiplanar imaging yields information regarding implant placement and articular reduction that is more detailed and accurate than standard fluoroscopy and is comparable to CT.

Influence of lower limb rotation in navigated alignment analysis: implications for high tibial osteotomies

Inaccurate coronal plane realignment is a common problem after high tibial osteotomy. It has been shown that lower limb rotation has an effect on the two-dimensional measurement of lower limb alignment. Although alignment errors are known to occur due to limb rotation, the magnitude of this effect is unknown. Navigation systems allow for the measurements of coronal plane alignment and dynamically rotational and sagittal plane. Our study evaluated the effect of rotational leg movements on coronal plane alignment as determined by image-free navigation. We hypothesized that a linear relationship exists between rotation and angular measurements. Eight cadavers were used, while three test conditions of the complete lower limbs were established: (1) solid knee arthrodesis, (2) provisional knee arthrodesis and (3) unconstrained knee conditions. Navigated measurements of coronal and sagittal lower limb axis were done initially without knee flexion for defined internal/external rotations of 5 degrees, 10 degrees and maximal values for all test series. Repeated test for the unconstrained knee included stepwise knee flexion of 5 degrees, 10 degrees and 20 degrees. Statistical analysis comparing the test conditions 1, 2 and 3 and comparison between flexion movements of the unconstrained knee were done. Results revealed no significant differences between the different rotations of test condition 1 (mean 0.34 degrees, SD 0.23, range, 0 degrees-0.8 degrees). Condition 2 similarly did not result in significant deviations (mean 0.51 degrees, SD 0.24, range 0.1 degrees-0.9 degrees). Measurement deviations ranging from 0.4 degrees to 4.3 degrees were found for condition 3, the unconstrained knee. However, no statistically different testings from the arthrodesed knee were found (P=0.099-0.410). Knee flexion from 5 degrees, 10 degrees or 20 degrees, showed significant deviations (P<0.05) for all rotations at all degrees of flexion. Rotation and flexion of 5 degrees led to significant alignment errors of 3.4 degrees and 2.8 degrees, respectively, for internal and external rotations. Measurement failures due to the rotational movements of 1 degree-4 degrees might add to additional sources of errors causing relevant under- or over-corrections of the mechanical leg axis. Discrepancies of the axis due to rotational movements as well as flexion of the knee joint can be avoided and corrected immediately with the help of navigation.

Die navigierte Scaphoidschraube

INTRODUCTION

Up to now, the use of navigation systems for the placement of scaphoid screws has been impossible, mainly because there have been no ways of fixing the reference markers. Faulty placement rates in internal fixation of the scaphoid show there is a current need for a 3D image-based navigation system and intraoperative monitoring of how successful the procedure will be. For this reason, we have developed a new radiotransparent hand fixation device (Scaph-Splint), which allows reliable and accurate drilling of the scaphoid using 3D navigation. Tests of this device and the simultaneous precise placement of screws securing an internal fixation device are described in this paper.

MATERIAL AND METHODS

Relative movements between the wrist and fixation device were measured with a 3-D ultrasound motion analyser system. Five cadaveric upper extremity specimens were then used for further navigated test applications. Each specimen was placed in the fixation device, and both the forearm and hand were secured to the two surfaces, with the wrist in approximately 80 degrees of extension. A reference marker was then securely fixed to the fixation device. A commercial navigation system and 3-D fluoroscopic imaging were used for each trial. Under navigation, the scaphoid was drilled in retrograde fashion, and a screw was placed into the drilled hole. Following screw placement, a 3D scan was performed to evaluate its position. The screw placement was analysed blindly to optimal placement and drill or screw perforation, and the image quality was rated on a visual analog scale (VAS).

RESULTS

There were few artefacts, and the image quality of the 3-D scan was judged as as good (VAS 79). Deviations of >or=0.2 mm between planned trajectory and drilling tunnal were not found in any of the specimens; there were deviations of >or=1 mm in one case, and all other cases showed deviations of <or=1 mm. There were no registration failures of the navigation system, indicating that no loosening of the reference marker or movement of the hand occurred. There was one case of scaphoid perforation at the distal pole.

DISCUSSION

We found that the Scaph-Split allowed complete immobilisation of the hand and carpus. This allowed for adequate reference tracker stability and subsequent successful 3D navigated fluoroscopic drilling and screw placement in the scaphoid. While further tests on fresh-frozen cadavers is warranted, this technique may prove clinically to be very useful for surgeons treating scaphoid fractures.

[A new parallel drill guide for navigating femoral neck screw placement. Development and evaluation]

BACKGROUND

Trauma navigation applications employ conventional mechanical surgical instruments for the simulation of drilling trajectories. Few complex mechanical targeting instruments, such as guides with fixed angles or with multiple parallel cannulas, have been adapted into trauma navigation systems. We have integrated a complex mechanical tool, the parallel drill guide (PDG) for the minimally invasive treatment of femoral neck fractures, into a trauma navigation module. The combined advantage of a complex yet commonly used mechanical tool with the benefits of fluoroscopic navigation was evaluated.

MATERIAL AND METHODS

To adapt the conventional PDG to a fluoroscopic navigation system, the instrument was fitted with a non-detachable reflective marker array. Navigation engineers developed custom software to enable visualization of the navigated PDG. A comparison of conventional versus navigated PDG techniques was performed on plastic bone models and cadavers. No software or mechanical failures occurred with the navigated PDG procedures.

RESULTS

While the total operative time was 30% more with navigation compared with conventional techniques, the total radiation time for the navigated group was reduced by more than 60%. This study demonstrates the successful integration of a cannulated parallel drill guide with a fluoroscopic navigation system.

CONCLUSION

The continuous display of the complex PDG mechanical instrument, with multiple parallel virtual trajectories, enables safe and accurate parallel screw placement. The integration of complex mechanical instrumentation with navigation for the accurate placement of hardware represents an attractive direction in multiple trauma applications.

Navigated percutaneous pelvic sacroiliac screw fixation: experimental comparison of accuracy between fluoroscopy and Iso-C3D navigation

Percutaneous sacroiliac screw fixation is technically demanding and can result in complications mainly related to imaging problems. Furthermore, the conventional technique performed using fluoroscopic control is associated with a long radiation exposure. The purpose of this study was to evaluate the accuracy of two navigation technologies used in traumatology; fluoroscopy and Iso-C3D navigation. A total of 40 screws were placed (20 with Iso-C3D, 20 with 2D fluoroscopy) at levels S1 and S2. With both technologies, all S1 screws could be placed correctly, but four (10%) incorrect placements were seen at S2 with fluoroscopy navigation. With all Iso-C3D navigated drillings, no perforation was seen. Iso-C3D navigation therefore proved superior to 2D fluoroscopy navigation for sacroiliac screw fixation in an experimental set-up designed to assess accuracy.

Accuracy analysis of Iso-C3D versus fluoroscopy-based navigated retrograde drilling of osteochondral lesions

The aim of this pilot study was to evaluate the accuracy of two different methods of navigated retrograde drilling of talar lesions. Artificial osteochondral talar lesions were created in 14 cadaver lower limbs. Two methods of navigated drilling were evaluated by one examiner. Navigated Iso-C3D was used in seven cadavers and 2D fluoroscopy-based navigation in the remaining seven. Of 14 talar lesions, 12 were successfully targeted by navigated drilling. In both cases of inaccurate targeting the 2D fluoroscopy-based navigation was used, missing lesions by 3 mm and 5 mm, respectively. The mean radiation time was increased using Iso-C3D navigation (23 s; 22 to 24) compared with 2D fluoroscopy-based navigation (14 s, 11 to 17).

[A web-based e-learning tool in academic teaching of trauma surgery. First experiences and evaluation results]

There are lots of possibilities for universities to offer contents of teaching to students by the Internet. Often the students can download slides or a special lecture note from the intranet of the university. Another way is to make a movie of the lecture and post this lecture movie on the Internet. In the Hanover Medical School we employed an alternative. It was developed by the Trauma Surgery Clinic and the Institute of Medical Informatics at the Hanover Medical School. Our goal was to use just one web-based content resource for the lecture and for the work at home. The Institute of Medical Informatics used a web-based content management system (CMS) Schoolbook to implement this e-learning application.Since October 2005 the Trauma Surgery Schoolbook has been used in the lecture on trauma surgery in all terms, and we evaluated the academic year 2005/2006. The results of the evaluation showed us that the students were very interested in using this e-learning application. The possibility to reinforce the learning material at home is a good chance for the students. Also the organisation of lectures was improved because the materials were all in one place. The lecturer needs to learn several new tasks, but we also got a positive response. Our experiences of the last academic year showed that it was a good way to use one web-based content resource for teaching and learning in the context of a lecture.

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.

Reference marker stability in computer aided orthopedic surgery: a biomechanical study in artificial bone and cadavers

INTRODUCTION

In computer assisted orthopaedic surgery, rigid fixation of the Reference Marker (RM) system is essential for reliable computer guidance. A minimum shift of the RM can lead to substantial registration errors and inaccuracies in the navigation process. Various types of RM systems are available but there is little information regarding the relative stabilities of these systems. The aim of this study was to test the rotational stability of three commonly used RM systems.

MATERIALS AND METHODS

One hundred and thirty Synbones and 15 cadavers were used to test the rotational stability of three different RM systems (Schanz' screw, RM B and RM C adjustment systems). Using a specially developed testing device, the peak torque sustained by each RM system was assessed in various anatomical sites.

RESULTS

Comparison of means for Synbone showed that the RM C was the most stable (mean peak torque 5.60 +/- 1.21 Nm) followed by the RM B system (2.53 +/- 0.53 Nm) and the RM A (0.77 +/- 0.39 Nm) (p<0.01). The order of stability in relation to anatomical site was femoral shaft, distal femur, tibial shaft, proximal tibia, anterior superior iliac spine, iliac crest and talus. Results from the cadaver experiments showed similar results. Bi-cortical fixation was superior to mono-cortical fixation in the femur (p<0.01) but not the tibia (p=0.22).

CONCLUSION

The RM system is the vital link between bone and computer and as such the stability of the RM is paramount to the accuracy of the navigation process. In choosing RM systems for computer navigated surgery surgeons should be aware of their relative stability. Anatomical site of RM placement also affect the stability. Mono-cortical fixation is generally less stable than bi-cortical.