Pedicle screw accuracy in thoracolumbar fractures- is routine postoperative CT scan necessary?

BACKGROUND: While several studies report on accuracy rates of pedicle screws, risk factors associated with inaccurate pedicle screw positioning in patients with thoracolumbar fractures are reported rarely. CT scan as a routine postoperative control is advocated by various authors, however its necessity remains unclear. METHODS: Two hundred forty-five patients were included in this retrospective study. Percutaneous dorsal instrumentation was most commonly performed (n = 201). Classification of Zdichavsky et al. and Rao et al. were used to classify screw misplacement and anterior perforation was further evaluated according to the extent of perforation (< 2 mm; > 2 mm). Multivariate analysis was performed to identify risk factors for misplacement of screws. RESULTS: One thousand sixty-eight pedicle screws were inserted in 245 patients. Misplacement was found in 51 screws (4.8%) in 42 patients (17.1%) according to the classification of Zdichavsky et al. and in 75 screws (7.0%) in 64 patients (26.1%) according to the classification of Rao et al.. An anterior perforation of the vertebral cortex was found in 56 screws (5.2%). Multivariate analysis showed fracture location in the upper thoracic (p = 0.048) and lumbar spine (p = 0.013) to be the only independent predictors for screw misplacement. In addition a significant correlation between pedicle diameter and the occurrence of screw malposition was found (p = 0.003). No consequences were drawn from postoperative routine CT in asymptomatic patients. CONCLUSION: An overall low rate of screw misplacement was found with fracture location in the upper thoracic and lumbar spine being the only factors independently associated with the risk of screw misplacement. No consequences were drawn from postoperative routine CT in asymptomatic patients. Therefore its use has to be discussed critically.

[Early clinical care strategy for severely injured patients with abdominal trauma]. / Frühe klinische Versorgungsstrategien für schwerverletzte Patienten mit Abdominaltrauma.

BACKGROUND: The presence of abdominal injuries has a major impact on the mortality of severely injured patients. For injuries that require surgery, laparotomy is still the gold standard for early surgical care; however, there is increasing evidence that laparoscopy may be an alternative in the early clinical care of polytrauma patients. OBJECTIVE: The present registry-based study analyzed the utilization and the outcome of laparoscopy in severely injured patients with abdominal trauma in Germany. MATERIAL AND METHODS: A retrospective analysis of 12,447 patients retrieved from the TraumaRegister DGU® (TR-DGU) was performed. The primary inclusion criteria were an injury severity score (ISS) ≥ 9 and an abbreviated injury scale (AIS) [abdomen] ≥ 1. The included patients were grouped according to early treatment management: (1) laparoscopy, (2) laparotomy and (3) non-operative management (NOM). Finally, group-specific patient characteristics and outcome were analyzed. RESULTS: The majority of patients were treated by NOM (52.4%, n = 6069), followed by laparotomy (50,6%, n = 6295) and laparoscopy (0.7%, n = 83). The majority of laparoscopies were performed in patients with an AIS [abdomen] ≤ 3 (86.7%). The ISS of the laparoscopy group was significantly lower compared to that of the laparotomy and NOM groups (ISS 23.4 vs. 34.5 vs. 28.2, respectively, p ≤ 0.001). The standardized mortality rate (SMR), defined as the ratio between observed and expected mortality, was lowest in the patients receiving laparoscopy followed by laparotomy and NOM (SMR 0.688 vs. 0.931 vs. 0.932, respectively, p-value = 0.2128) without achieving statistical significance. CONCLUSION: Despite being rarely employed the data indicate the effectiveness of laparoscopy for the early treatment of severely injured, hemodynamically stable patients with an AIS [abdomen] ≤ 3.

Spinal cord injury without radiographic abnormality (SCIWORA) in adults: MRI type predicts early neurologic outcome.

OBJECTIVES: The present study aimed to analyse the clinical and neuroimaging features of a consecutive series of adult patients with spinal cord injury without radiographic abnormality (SCIWORA) receiving early magnetic resonance imaging (MRI), and to apply the recently proposed MRI classification system. METHODS: Grade of neurologic impairment at admission and discharge was reported according to the American Spinal Injury Association Impairment Scale (AIS). A detailed analysis and categorisation of the extra- and intramedullary MRI findings was performed, and the relationship between imaging type and neurological outcome was described. RESULTS: Twenty-six adult patients (17 male and 9 female) with SCIWORA were identified (mean age of 52 years). The distribution of the initial AIS grade was 8% A (n=2), 19% B (n=5), 31% C (n=8) and 42% D (n=11) at admission and 15% (n=4) C, 58% (n=15) D and 27% (n=7) E at discharge, respectively. Type I SCIWORA was found in 23% (n=6) and type II in 77% (n=20) (IIa: 0%, IIb: 25%, IIc: 75%). The mean improvement of AIS grade in patients with type I lesions was 1.5 (median 1, range 1-3) and 0.9 (median 1, range 0-3) in type II. CONCLUSION: The findings underline the prognostic role of early MRI for adult patients with SCIWORA and support the use of the recently introduced MRI classification system. LEVEL OF EVIDENCE: Prognostic study, level III.

The relationship between initial closed reduction and the surgical reconstruction of the radiocarpal joint line in distal radial fractures.

INTRODUCTION: Whilst initial closed reduction followed by definitive open fixation is widely applied in the treatment of distal radial fractures, the effect of the closed reduction on the reconstruction of the articular surface remains unclear. Our research questions were: METHODS: Palmar tilt and radiocarpal inclination of 425 patients were measured at admission, following initial closed reduction and after surgical reconstruction. RESULTS: Closed reduction increased palmar tilt by 12.1° and radial inclination by 2.7°. Open surgical reduction further corrected palmar tilt by 17.88° and radial inclination by 3.5°. Whilst there was no association between postoperative palmar tilt and initially achieved closed reduction, a significant association between radial inclination following closed reduction and surgical fixation was found. CONCLUSION: Our retrospective study challenges the existence of a relationship between the initial closed reduction and the reconstruction of the anatomic joint line in surgically treated distal radial fractures.

The validity of a novel radiological method for measuring femoral stem version on anteroposterior radiographs of the hip after total hip arthroplasty.

Femoral stem version has a major influence on impingement and early post-operative stability after total hip arthroplasty (THA). The main objective of this study was to evaluate the validity of a novel radiological method for measuring stem version. Anteroposterior (AP) radiographs and three-dimensional CT scans were obtained for 115 patients (female/male 63/72, mean age 62.5 years (50 to 75)) who had undergone minimally invasive, cementless THA. Stem version was calculated from the AP hip radiograph by rotation-based change in the projected prosthetic neck-shaft (NSA*) angle using the mathematical formula ST = arcos [tan (NSA*) / tan (135)]. We used two independent observers who repeated the analysis after a six-week interval. Radiological measurements were compared with 3D-CT measurements by an independent, blinded external institute. We found a mean difference of 1.2° (sd 6.2) between radiological and 3D-CT measurements of stem version. The correlation between the mean radiological and 3D-CT stem torsion was r = 0.88 (p < 0.001). The intra- (intraclass correlation coefficient ≥ 0.94) and inter-observer agreement (mean concordance correlation coefficient = 0.87) for the radiological measurements were excellent. We found that femoral tilt was associated with the mean radiological measurement error (r = 0.22, p = 0.02). The projected neck-shaft angle is a reliable method for measuring stem version on AP radiographs of the hip after a THA. However, a highly standardised radiological technique is required for its precise measurement.

[Diagnosis and treatment of abdominal trauma]. / Diagnostik und Therapie des Abdominaltraumas.

Abdominal trauma represents the leading cause of haemorrhagic shock in the severely injured patient and is associated with high mortality and morbidity rates. The trauma surgeon has a central role in the multidisciplinary team addressing the specific diagnostic and therapeutic needs of patients with abdominal trauma. The management of blunt and penetrating abdominal trauma has undergone substantial changes in recent decades. Major innovations have been established in the field of diagnostic imaging and of nonoperative interventions such as angioembolization and endoscopic procedures. Another key development is the introduction of the damage control concept for the care of patients with abdominal trauma. The present manuscript comprises a review of the current management of abdominal trauma with an emphasis on diagnostic and therapeutic innovations.

[Denervation of the patella: influence on mid-term results after total knee arthroplasty]. / Retropatellare Denervierung : Einfluss auf die mittelfristigen Ergebnisse von Knietotalendoprothesenimplantationen.

BACKGROUND: The purpose of the study was to determine possible differences in the mid-term results of total knee arthroplasty in patients treated with and without denervation of the patella. PATIENTS AND METHODS: This study included 80 total knee replacements in 71 patients who were treated with total knee replacement, either with (n = 40) or without (n = 40) simultaneous denervation of the patella out of a total population with 122 knee replacements in 100 patients. Comparability of both groups was achieved by applying matching criteria. All patients were reviewed by isokinetic tests, physical and radiological examination. The mean follow-up time was 2.2 years. RESULTS: The mean hospital for special surgery (HSS) score revealed no statistically significant differences between both groups (with denervation 77.9 ± 11.1 and without denervation 77.8 ± 11.0, p = 0.976). The isokinetic torque measurements with low angle velocity (60°/s) indicated slightly higher values during extension (60.2 ± 32.2 Nm versus 55.8 ± 25.2 Nm, p = 0.497) and flexion (52.4 ± 28.3 Nm versus 46.1 ± 22.3 Nm, p = 0.272) movements of the affected knee joint. However, the differences did not reach statistical significance. At high angle velocity (180°/s) no differences could be found between both groups. No cases of postoperative necrosis of the patella were observed. Anterior knee pain after denervation was reported in 6 cases (15 %) compared to 10 cases (25 %) in patients who were treated without denervation (p = 0.402). CONCLUSION: No statistically significant differences could be found between patients with and without denervation of the patella for total knee arthroplasty.

Mechanism of injury and treatment of trauma-associated acute compartment syndrome of the foot.

Acute compartment syndrome (ACS) of the foot represents a rare complication following trauma of the lower extremity. Early diagnosis and treatment are necessary to prevent poor outcome. The study was conducted to describe etiology and treatment of foot ACS. In the current study, patients diagnosed with and treated for ACS between 1st December 2000 and 30th September 2007 were included. Mechanism of injury, additional injuries and treatment was analyzed. We included 31 patients (21 males) with a mean age of 33.8 ± 16.9 years. Most injuries were caused by a motor vehicle accident, while nearly 20 % occurred after a low-energy mechanism. Multiple injuries with a mean ISS of 19.5 ± 11.0 were present in 14 patients. Superficial infections occurred in 6 feet, while a deep infection only developed in one patient. Acute compartment syndrome of the foot has a low incidence. A thorough clinical examination in patients on risk is required to provide timely diagnosis and adequate surgical decompression.

[Influence of comorbidities and delay in surgical treatment on mortality following femoral neck fracture]. / Der Einfluss von Begleiterkrankungen und operativem Versorgungszeitpunkt auf die Mortalität bei Patienten mit Schenkelhalsfraktur.

BACKGROUND: Hip fractures typically occur in geriatric patients representing an increasing medical as well as socioeconomic challenge. PATIENTS AND METHODS: In order to reveal the influence of considerable comorbidities and the time of surgery in the treatment of geriatric hip fractures we analysed patients treated between 1993 and 2008 at a level I trauma centre. RESULTS: 654 patients with isolated hip fractures were included. Surgical treatment was performed with osteosynthetic stabilisation in 55.5 % (n = 363) and with endoprosthetic implants in 44.5 % (n = 291). The presence of pulmonary, psychiatric and metabolic/endocrinological comorbidities resulted in delayed treatment. If an early surgical treatment was performed within the first 12 hours after hospital admission, long-term survival was significantly improved (p = 0.02). A regression analysis revealed a statistical trend towards an increased mortality of 0.2 % per hour delay after hospital admission. The presence of considerable comorbidities and surgical treatment with endoprosthetic implants (odds ratio 1.611) were proven as independent mortality factors. CONCLUSION: The present study supports the guideline of early surgical treatment of geriatric hip fractures. Emphasising the incidence of in-hospital complications and the mortality after endoprosthetic treatment, osteosynthetic fracture stabilisation should be considered in the presence of considerable morbidity and pre-surgical immobilisation.

[What medical students want - evaluation of medical recruitment ads by future physicians]. / Was Medizinstudierende wollen - Einschätzung ärztlicher Stellenanzeigen durch angehende Ärztinnen und Ärzte der Humanmedizin.

OBJECTIVE: Three-quarters of all hospitals in Germany are now struggling to fill open positions for doctors. The medical job ad is a vital tool for human resources marketing and an important image factor. The present study examines the importance of information and offers in medical recruitment ads on application decisions by medical students. METHOD: A total of 184 future physicians from clinical semesters participated voluntarily in an anonymous cross-sectional survey. Using a standardised questionnaire, the importance of 49 -individual items extracted from medical recruitment ads were rated with the help of a 4-point Likert Scale. Finally, the study participants prioritised their reasons for an application as a physician. RESULTS: Primary influence on the application decision on medical recruitment ads by medical students had offers/information in relation to education and training aspects and work-life balance. Payment rates for physicians and work load played an important role for the application motivation. Additional earnings for, e. g., emergency calls, providing of medical expertise and assistance with housing, relocation and reimbursement of interview expenses were less crucial. In prioritising key reasons for selecting a prospective employer "regular working hours," an "individual training concept" and an "attractive work-life balance" scored the highest priority. The "opportunity for scientific work" was assigned only a small significance. CONCLUSION: High importance for the application decision by future physicians on medical recruitment ads is placed on jobs with an opportunity for personal development and aspects that contribute to work-life balance.

The impact of chemical synovectomy with sodium morrhuate on human chondrocytes and cartilage in vitro.

The vessel sclerosing property of sodium morrhuate is useful in treatment of recurrent joint effusions particularly in cases of knee joint effusions. It also can be employed as an addition to surgical synovectomy. Little is known about the effects of this drug on cartilage. This study was designed to investigate the cytotoxic impact of sodium morrhuate on human chondrocytes and cartilage tissue in vitro. Primary chondrocytes from 13 patients were isolated and cultivated in three-dimensional alginate cultures. Furthermore, femoral cartilage explants of 10 patients were cultivated in vitro. Both chondrocytes and cartilage explants were exposed to mixture of sodium morrhuate and mepivacaine in different concentrations simulating chemical synovectomy. After 48 h, cell proliferation, viability, and cytotoxicity were measured. The cartilage specimens were analyzed for apoptosis by immunohistochemistry. Up to a dilution of 1:600, cells were found to be 100 % viable with a proliferation rate of 74 % compared to controls. From 1:400 onwards, a significant increase in LDH release was measured which reached at dilution of 1:200 74 % of high control, whereas histological examination showed no proof of apoptosis or necrosis in cartilage tissue. The results of this in vitro study demonstrate that the cytotoxic effects of sodium morrhuate on human chondrocytes, which lack their original extracellular matrix, manifest between dilutions of 1:500 and 1:400 and increase with higher concentrations of the drug. This effect was not found for cartilage explants, though.

[The oncofetal gene survivin - a possible target gene for regenerative therapy concepts in cartilaginous tissue]. / Das "onkofetale" Gen Survivin - ein mögliches Ziel-Gen regenerativer Therapiekonzepte im Gelenkknorpel.

Survivin, the smallest member of the inhibitor of the apoptosis protein gene family (IAP) is a key molecule for mammalian cell cycle regulation and cellular survival. Of note these functions have been thought to be limited to embryonic and malignant tissues. However, a growing body of evidence indicates a limited expression of survivin in some highly specific adult tissues and cells. In the present study it has been demonstrated that the antiapoptotic protein survivin is re-expressed in osteoarthritic human cartilage and primary human chondrocytes. Furthermore, the data indicated that survivin significantly affects cell cycle regulation and cellular survival. The modulation of survivin expression and function in cartilaginous tissues might be important for understanding osteoarthritis and the development of regenerative strategies.

[Revision implants of the future: trends and new developments]. / Revisionsimplantate der Zukunft: Trends und neue Entwicklungen.

According to current prognostic studies the numbers of revision operations of hip and knee arthroplasty will increase worldwide. As many patients undergo several revisions and become older at the same time, orthopedic surgeons will have to cope with vast bony defects during operations. The introduction of highly porous metals as surface layer or metal augments has facilitated primary stabilization of prostheses. Short and mid-term results of these new products are promising. New developments in coatings, such as cationic antimicrobial peptides represent new alternatives for antibacterial therapy of periprosthetic infections and increase osteointegration of prosthesis components. Furthermore, the new revision systems have a modular design and can be individually adapted to the patient's bony conditions during operations. In most cases this can be done without cement or in a hybrid technique.

[Patient satisfaction and muscle torque after total knee replacement in dependence on body mass index]. / Patientenzufriedenheit und Muskelkraft nach Knietotalendoprothese in Abhängigkeit vom Body-Mass-Index.

AIM: In a monocentric study, we investigated patient satisfaction, clinical outcome and isokinetic muscle torque in dependence on the body mass index (BMI) in the mid-term outcome after total knee arthroplasty. PATIENTS AND METHODS: A group-matched study with two groups (each 40 knee arthroplasties in 40 patients) with a normal body mass index (BMI 20-25) and above 25 was conducted. The groups were matched for sex, diagnosis and age. Satisfaction, HSS score and isokinetic torque parameters with the Cybex 340 system were measured. RESULTS: There were no differences in the demographic data except for BMI. The HSS score was significantly lower in the overweight group (p = 0.04). Also there were more patients with an HSS score below 60 (bad result) in the group with the higher BMI (0 vs. 9, p = 0.002). Only one patient was not satisfied in the normal weight group, whereas 9 patients in the group BMI > 25 were not satisfied (p = 0.014). No differences between the groups could be found in maximum torque, work and power. CONCLUSION: The patient satisfaction was much lower in patients with BMI higher than 25. There were no differences between the groups in isokinetic torque parameters.

[Traumatology and sport injuries in professional and amateur show-jumping competitors]. / Sportverletzungen und Sportschäden bei Amateur- und Profispringreitern.

The objective of this study was to investigate the frequency, extent, and effective preventive measures of sport injuries in professional and amateur-show jumping competitors. In a retrospective study design, 264 show-jumping riders (105 professionals, 159 amateurs) were interviewed by means of a standardised questionnaire. In total, 636 injuries were reported in detail. Injuries were categorised into severity grade I (36.0 %) (not requiring medical attention), grade II (34.6 %) (single medical treatment), grade III (20.9 %) (several outpatient medical treatments) and grade IV (8.5 %) (requiring hospitalisation). Specifically, 40.9 % of the reported injuries to professional riders and 23.9 % of those to amateurs were classified as severe (grade III or IV). The time-related injury rate in professional athletes was 1.1 / 1000 h compared to 2.1 / 1000 h in amateurs. The predominating types of sustained injuries were contusions (22 %), articular sprains (16 %) and abrasions (16 %). Fractures were reported in 12 % of all injuries. There were 95 head injuries (15 %). The ratio between injured lower and upper extremities was 1.12 in professional athletes and 0.85 in amateur riders. Persistent pain at any site was reported by 33.7 %. Helmet use was reported in 89 % of professional and 94 % of amateur riders. In spite of a high level of expertise and longer experience, professional show-jumping riders seem to be at higher risk for sustaining severe injuries. Both performance-oriented style of riding and readiness to assume risk are presumably factors leading to this increased rate of severe injuries. No significant differences were seen between the use of safety measures in amateur and professional athletes. While most of the riders indicated the regular use of protective head gear, craniocerebral injuries are still frequent. Taken together, besides a circumspect riding style, the wearing of helmets remains the most important safety measure.

[Principles and new concepts in computer-navigated total hip arthroplasty]. / Grundlagen und neue Konzepte in der computernavigierten Hüftendoprothetik.

Combined component placement of cup and stem is closely correlated to stability, functionality and wear in total hip replacement (THA). Computer-navigated orthopedic surgery offers a reliable control method for a complex three-dimensional situation. Imageless navigation systems without the need of preoperative or intraoperative image acquisition and exposure to radiation have been proven to increase the accuracy of positioning the acetabular component and measure intraoperative leg length and offset changes precisely. A new development in this field is the noninvasive external femoral reference marker array system in conjunction with an imageless measurement technique. The future generation of imageless navigation systems will switch from simple measurement tasks to an integral part of the surgical process in navigated THA. The aim will be to find an optimized complementary component orientation with improved postoperative functionality and optimized range of motion without impingement.

[Minimally invasive surgery in total hip arthroplasty : Surgical technique of the future?]. / Minimalinvasive Operationstechniken in der Hüftgelenktotalendoprothetik : Operationstechniken der Zukunft?

AIM: A selective analysis of the latest literature was carried out including prospective clinical controlled studies on the comparison between minimally invasive total hip arthroplasty (MIS) and the conventional technique. METHODS: An online data base search for controlled study designs within the last 3 years (2009-2011) which compared MIS with standard procedures was performed. Data such as operation time, blood loss, Harris hip score, complications and implant positioning were compared. RESULTS: A total of 11 studies which compared the results of 387 MISs and 264 operations on hips with the standard technique were analyzed. In the majority of the studies reduced levels of creatine kinase and myoglobin as well as reduced intraoperative blood loss were reported. In the early postoperative period up to postoperative week 6 significant advantages in the Harris hip score were reported for the MIS patients. Postoperative complications and implant positioning were comparable in both groups. The operation time was significantly longer in the MIS group for some studies. CONCLUSIONS: Minimally invasive techniques in total hip arthroplasty are nowadays no longer seen as just cosmetically attractive but rather as a real improvement for the clinical outcome. In this respect prospective clinically controlled studies within the last 3 years showed advantages in the early postoperative period.

[Patellofemoral pain after total knee arthroplasty: clinical pathway and review of the literature]. / Patellofemoraler Schmerz nach primärer Knieendoprothetik : Behandlungsalgorithmus und Literaturüberblick.

Total knee arthroplasty (TKA) is an operation with a high gain in quality of life. However, some patients suffer from pain, limited range of motion, instability, infections or other postoperative complications. Patellofemoral pain (PFP) in particular is a common complication after TKA and is often responsible for revision surgery. In particular increasing and localized contact pressure and patella maltracking are held accountable for patellofemoral pain but the reasons are various. Diagnostics and therapy of patellofemoral pain is not easy to handle and should be treated following a clinical pathway. We suggest that patients with patellofemoral pain should be classified into four groups according to the suspected diagnosis after basic diagnostic measures as 1) tenidinosis, 2) mechanical reasons, 3) intraarticular non-mechanical reasons and 4) neurogenic psychogenic reasons. Efficient application of special diagnostic measures and further therapy is facilitated by this classification.