A suture anchor-based repair technique for type IV jersey finger injuries: a biomechanical investigation.

The aim of this biomechanical investigation was to evaluate a repair technique for type IV FDP tendon avulsions using a suture anchor, addressing the bony and the tendinous aspect of this injury simultaneously. In 45 distal phalanges from human anatomical specimens the injury was simulated and repairs were performed with a suture anchor using an innovative technique, interosseous sutures and a combination of screws and an interosseous suture. Repetitive loading for 500 cycles simulated postoperative mobilization. Repairs were loaded to failure thereafter. Elongation of the tendon-suture complex, gap formation at the bone-bone contact line and at the bone-tendon insertion line, load at first noteworthy displacement (2 mm), load at failure and the mechanism of failure were assessed. The suture anchor technique was superior biomechanically considering load at failure (mean: 72.8 N), bony gap formation (mean: 0.1 mm) as well as tendinous gap formation (mean: 0.7 mm), implying a preferable stability of the repair. Overall, this study demonstrates good ex vivo mechanical stability for a proposed suture anchor repair technique for type IV FDP tendon avulsion injuries, which might enable early postoperative mobilization in patients. The technique's subcutaneous implant placement and low implant load are expected to reduce potential complications observed in other commonly used repair techniques. This approach warrants further evaluation in vivo.

IL-33 and its increased serum levels as an alarmin for imminent pulmonary complications in polytraumatized patients.

Background: According to recently published findings, we hypothesized that serum interleukin-33 (IL-33) may qualify for predicting pulmonary complications in polytraumatized patients. Methods: One hundred and thirty patients (age ≥ 18 years, ISS ≥ 16) were included in our prospective analysis after primary admission to our level I trauma center during the first post-traumatic hour. Serum samples immediately after admission and on day 2 after trauma were obtained and analyzed. Results: Median initial IL-33 levels (in picograms per milliliter) were higher in polytrauma victims (1) with concomitant thoracic trauma [5.08 vs. 3.52; p = 0.036], (2) sustaining parenchymal lung injury (PLI) [5.37 vs. 3.71; p = 0.027], and (3) developing acute respiratory distress syndrome (ARDS) [6.19 vs. 4.48; p = 0.003], compared to the respective rest of the study group. The median initial IL-33 levels were higher in patients experiencing both PLI and ARDS compared to those sustaining PLI and not developing ARDS [6.99 vs. 4.69; p = 0.029]. ROC statistics provided an AUC of 0.666 (p = 0.003) and a cut-off value of 4.77 (sensitivity, 71.8%; specificity, 75.7%) for predicting ARDS. Moreover, a higher initial median IL-33 level was revealed in the deceased compared to the survivors [12.25 vs. 4.72; p = 0.021]. ROC statistics identified the initial level of IL-33 as a predictor of death with 11.19 as cut-off value (sensitivity, 80.0%; specificity, 80.0%; AUC = 0.805; p = 0.021). Conclusions: Following tissue damage, IL-33 is abundantly released in the serum of polytraumatized patients immediately after their injuries occurred. As initial IL-33 levels were particularly high in individuals experiencing both PLI and ARDS, IL-33 release after trauma seems to be involved in the promotion of ARDS and might serve already at admission as a solid indicator of impending death in polytraumatized patients.

The impact of polytrauma on sRAGE levels: evidence and statistical analysis of temporal variations.

BACKGROUND: According to recently published findings, levels of the soluble receptor of advanced glycation end products (sRAGE) and its clearance from the blood may reflect the evolution of lung damage during hospitalization. Thus, the objective of this study was to reveal the course of sRAGE levels over the first three posttraumatic weeks, focusing on the severity of thoracic trauma and the development of acute respiratory distress syndrome (ARDS) and/or pneumonia. METHODS: Twenty-eight consecutive surviving polytraumatized patients suffering thoracic trauma, age ≥ 18 years, Injury Severity Score ≥ 16, and directly admitted to our level I trauma center were enrolled in this prospective study. Blood samples were taken initially and on days 1, 3, 5, 7, 10, 14, and 21 during hospitalization. Luminex multi-analyte-technology was used for biomarker analysis. RESULTS: Common to all our patients was an almost continuous decline of sRAGE levels within the first five posttraumatic days. Day 0 levels in polytrauma victims with severe thoracic trauma were more than twice as high than in those suffering mild thoracic trauma (p = 0.035), whereas the difference between the two groups did not reach significance from day 1. Neither the development of ARDS and/or pneumonia nor the necessity of secondary surgery did result in significant differences in sRAGE levels between the subgroups with and without the particular complication at any time point. CONCLUSIONS: sRAGE levels assessed immediately after hospital admission might serve as a diagnostic marker for the vehemence of impacts against the chest and thus might be applied as an additional tool in diagnosis, risk evaluation, and choice of the appropriate treatment strategy of polytraumatized patients in routine clinical practice.

Introduction of a new repair technique in bony avulsion of the FDP tendon: A biomechanical study.

The purpose of this study was to determine the biomechanical characteristics of an innovative surgical technique based on a tension banding principle using a suture anchor in the repair of bony avulsions of the flexor digitorum profundus tendon. After injury simulation in 45 fresh frozen distal phalanges from human cadavers, repair was performed with minifragment screws, interosseous sutures and the innovative technique (15 per group). All repairs were loaded for a total of 500 cycles. Subsequently the specimens were loaded to failure. Load at failure, load at first noteworthy displacement (>2 mm), elongation of the system, gap formation at the avulsion site, and the mechanism of failure were assessed. The new techniques' superior performance in load at failure (mean: 100.5 N), load at first noteworthy displacement (mean 77.4 N), and gap formation (median 0 mm) was statistically significant, which implies a preferable rigidity of the repair. No implant extrusion or suture rupture during cyclic loading were recorded when the new technique was applied. This innovative repair technique is superior biomechanically to other commonly used surgical tendon reattachment methods, particularly with respect to an early passive mobilisation protocol. Further, due to its subcutaneous position, reduction of complications may be achieved.

Treatment of air leak in polytrauma patients with blunt chest injury.

INTRODUCTION: Precise diagnostics and an adequate therapeutic approach are mandatory in the treatment of air leak in polytrauma patients with blunt chest trauma. The aim of this study was to evaluate the incidence, characteristics, and management of air leak following this injury pattern. PATIENTS AND METHODS: Data from 110 polytrauma patients was collected retrospectively. Fifty-four patients received initial treatment by chest tube placement for pneumothorax. These patients were classified into two groups, one with severe air leak and one with minor air leak. An evaluation of injury pattern, chest wall injuries in particular, duration of air leak, reason for drainage maintenance in place, hospital length of stay, ICU stay, ventilator duration, type of treatment, and the delay to surgical intervention was performed. RESULTS: Whereas 4 patients showed severe air leak and were subsequently scheduled for timely surgical intervention, the remaining 50 patients only showed minor air leak. Only 7 patients with minor air leak suffered from prolonged air leak (>5days), which spontaneously resolved in all of them after a mean duration of 7.7days (range 6-12days). Absence of a prolonged air leak resulted in a shorter length of stay and a shorter duration of mechanical ventilation, although no statistical significance was observed. CONCLUSIONS: Early spontaneous cessation of most minor air leaks as well as early surgical intervention for severe air leak lead to very satisfactory patient outcomes with a relatively short hospital stay in our patients. We therefore advocate early surgery for lacerations of the pulmonary parenchyma resulting in severe air leak, whereas minor air leaks can usually be treated conservatively.

Club cell protein 16 and cytokeratin fragment 21-1 as early predictors of pulmonary complications in polytraumatized patients with severe chest trauma.

BACKGROUND: Acute respiratory distress syndrome (ARDS) and pneumonia have a great impact on the treatment regimen of polytraumatized patients with severe chest trauma. The objective of our study was to determine whether biomarker levels assessed shortly after multiple trauma may predict the occurrence of these conditions. METHODS AND FINDINGS: Our patient population included 71 men and 30 women (mean age, 40.3 ± 15.8 years) with an Injury Severity Score that ranged from 17 to 59 and an Abbreviated Injury Scale Thorax of at least 3. They were admitted to our level I trauma center within one post-traumatic hour and survived for at least 24 hours after the trauma occurred. Thirty-five patients developed ARDS, 30 patients pneumonia and 21 patients both. Five individuals died during hospitalization. The levels of five selected biomarkers, which were identified by a literature search, were assessed at admission (initial levels) and on day 2 after trauma. We performed comparisons of medians, logistic regression analyses and receiver operating characteristic analyses for initial and day-2 levels of each biomarker. With regard to ARDS, initial levels of cytokeratin fragment 21-1, the soluble fragment of cytokeratin 19 (CYFRA21-1) and of the club cell protein 16 (CC16) provided significant results in each statistical analysis. With regard to pneumonia, each statistical analysis supplied significant results for both initial and day-2 levels of CYFRA21-1 and CC16. Consistently, initial CYFRA21-1 levels were identified as the most promising predictor of ARDS, whereas day-2 CC16 levels have to be considered as most appropriate for predicting pneumonia. CONCLUSIONS: CYFRA21-1 levels exceeding cut-off value of 1.85 ng/ml and 2.49 ng/ml in the serum shortly after multiple injury occurred may identify polytraumatized patients at risk for ARDS and pneumonia, respectively. However, CC16 levels exceeding 30.51 ng/ml on day 2 may allow a firmer diagnosis for the development of pneumonia.

Thoracic trauma and acute respiratory distress syndrome in polytraumatized patients: a retrospective analysis.

BACKGROUND: Although thoracic trauma has often been associated with the development of acute respiratory distress syndrome (ARDS) in general, its impact on ARDS in combination with severe concomitant injuries has still to be elucidated. Therefore, the objective of this study was to determine the frequency of thoracic trauma and ARDS in polytraumatized patients, and to evaluate the impact of thoracic trauma on the occurrence and the onset of ARDS. METHODS: Included in this retrospective cohort study were all polytraumatized patients over 18 years of age, with an injury severity score (ISS) of at least 16, who were admitted to our level I trauma center over a three-year time period. RESULTS: Two hundred and eighty-eight patients met the inclusion criteria. 54.9% suffered from thoracic trauma, 51.7% developed ARDS, 21.5% pneumonia and 0.7% pulmonary embolism. Independent of the ISS, the presence of thoracic trauma increased the odds of ARDS occurrence (OR=2.242; 95% CI: 1.381-3.640; P<0.001) and resulted in a significantly earlier onset of ARDS (median, day 2 vs. day 3; P<0.01). Of those patients suffering from ARDS, ventilation time and length of stay at the ICU were longer if a concomitant thoracic injury was present (P<0.001). In general, ARDS was diagnosed prior to pneumonia and was therefore identified as its risk factor (OR=11.033; 95% CI: 4.812-25.299; P<0.001). Finally, an overall mortality rate of 21.2% was observed, which was neither affected by thoracic trauma nor ARDS. CONCLUSIONS: Thoracic trauma was identified as major risk factor for ARDS occurrence and earlier onset in polytrauma victims.

Lessons from a large trauma center: impact of blunt chest trauma in polytrauma patients-still a relevant problem?

BACKGROUND: Thoracic trauma is the third most common cause of death after abdominal injury and head trauma in polytrauma patients. The purpose of this study was to investigate epidemiological data, treatment and outcome of polytrauma patients with blunt chest trauma in order to help improve management, prevent complications and decrease polytrauma patients' mortality. METHODS: In this retrospective study we included all polytrauma patients with blunt chest trauma admitted to our tertiary care center emergency department for a 2-year period, from June 2012 until May 2014. Data collection included details of treatment and outcome. Patients with chest trauma and Injury Severity Score (ISS) ≥18 and Abbreviated Injury Scale (AIS) >2 in more than one body region were included. RESULTS: A total of 110 polytrauma patients with blunt chest injury were evaluated. 82 of them were males and median age was 48.5 years. Car accidents, falls from a height and motorbike accidents were the most common causes (>75%) for blunt chest trauma. Rib fractures, pneumothorax and pulmonary contusion were the most common chest injuries. Most patients (64.5%) sustained a serious chest injury (AISthorax 3), 19.1% a severe chest injury (AISthorax 4) and 15.5% a moderate chest injury (AISthorax 2). 90% of patients with blunt chest trauma were treated conservatively. Chest tube insertion was indicated in 54.5% of patients. The need for chest tube was significantly higher among the AISthorax 4 group in comparison to the AIS groups 3 and 2 (p < 0.001). Also, admission to the ICU was directly related to the severity of the AISthorax (p < 0.001). The severity of chest trauma did not correlate with ICU length of stay, intubation days, complications or mortality. CONCLUSION: Although 84.5% of patients suffered from serious or even severe chest injury, neither in the conservative nor in the surgically treated group a significant impact of injury severity on ICU stay, intubation days, complications or mortality was observed. AISthorax was only related to the rate of chest tube insertions and ICU admission. Management with early chest tube insertion when necessary, pain control and chest physiotherapy resulted in good outcome in the majority of patients.

Treatment options and outcome after bony avulsion of the flexor digitorum profundus tendon: a review of 29 cases.

INTRODUCTION: The objective of this retrospective review was to evaluate the functional and esthetic outcomes in patients with non- or minimally (<2 mm), and severely (>2 mm) displaced bony avulsions of the flexor digitorum profundus (FDP) tendon. MATERIALS AND METHODS: Between 1996 and 2010, 29 patients with a bony avulsion of the FDP tendon were treated. The displacement magnitude of the avulsed fragment determined, whether conservative or surgical treatment was performed. Persisting functional deficit, radiological findings, remaining disabilities using the Disability of the Arm, Shoulder, and Hand (DASH) score, as well as treatment-related deformities and complications were evaluated retrospectively and at a mean follow-up of 7 years. RESULTS: In 16 patients, conservative therapy by initial static splinting due to a fragment displacement of <2 mm was conducted. These patients reported no functional impairment at follow-up. In 13 cases, major displacement (>2 mm) of the bony fragment led to an open reconstruction of the avulsion injury either by screw fixation or a Lengemann pull-out wire. In a majority, an extension deficit in the DIP joint and a decrease of tip pinch strength by 25% was present at follow-up. In five patients, peri- or short-term postoperative complications occurred and in five, a nail deformity remained. DASH score revealed satisfying results after both therapeutic approaches. CONCLUSIONS: Conservative treatment in non- or minimally displaced avulsions leads to satisfying functional results. Patients receiving surgery after major fragment displacement need to be aware of a possible impaired ROM at the DIP joint. The use of the Lengemann pull-out wire may place patients at an increased complication risk and frequently induces nail deformities. LEVEL OF EVIDENCE: Therapeutic, level IV.

Soluble Receptor for Advanced Glycation End Products Quantifies Lung Injury in Polytraumatized Patients.

BACKGROUND: Biomarkers caused by blunt chest trauma might leak into the vascular compartment and therefore reflect the severity of parenchymal lung injury (PLI). Five promising proteins were preselected after a literature scan. The objective of our study was to identify a biomarker that is released abundantly into the serum shortly after trauma and reliably quantifies the loss of functional lung tissue. METHODS: Polytraumatized patients (aged ≥18 years, Injury Severity Score [ISS] ≥16) were included in our prospective observational study if they were admitted directly to our level I trauma center during the first hour after trauma occurred. Immediately after stabilizing the patient's condition, blood samples were taken and a whole-body computed tomographic (CT) scan was obtained. Biomarker levels were measured directly after admission and on day 2. PLI volume was calculated using volumetric analysis. RESULTS: One hundred thirty patients met the inclusion criteria. Compared with a matched healthy control population, median levels of the soluble receptor for advanced glycation end products (sRAGE) was almost 3 times higher and decreased by 41% on day 2. Higher initial median sRAGE levels were detected in patients with PLI compared with patients without PLI and in individuals with severe PLI compared with those with mild PLI. Spearman correlation analysis and a univariate linear log regression model revealed a significant correlation/equation between initial sRAGE levels and relative PLI volume. Receiver operating characteristic (ROC) statistics identified the initial sRAGE level as an indicator of severe PLI. CONCLUSIONS: sRAGE levels measured shortly after trauma seem to be a promising diagnostic tool to assess the severity of PLI in polytraumatized patients.

The clinical benefit of a follow-up thoracic computed tomography scan regarding parenchymal lung injury and acute respiratory distress syndrome in polytraumatized patients.

PURPOSE: To evaluate the increase of parenchymal lung injury (PLI) volume between the initial and a follow-up computed tomography (CT) scan and to ascertain which of the 2 scans was more appropriate to predict acute respiratory distress syndrome (ARDS). MATERIAL AND METHODS: From 2011 to 2015, polytraumatized patients (≥18 years; ISS ≥ 16) directly admitted to our level I trauma center were included in our prospective study if a follow-up CT scan was possible 24 to 48 hours after the trauma. The PLI volume was measured using volumetric analysis. Statistical calculations were performed to identify patients at risk for ARDS. RESULTS: One hundred thirty patients (mean age, 41.3 years; mean ISS, 31.9) met the inclusion criteria. Median relative PLI volume was higher in the follow-up than in the initial CTs (9.65% vs 4.84%; P = .001). The ARDS developed in 42 patients (32.3%). Their initial PLI volume was higher compared with those without ARDS (11.23% vs 2.14%; P < .0001). The ARDS incidence increased with increasing initial PLI volume. Receiver operating characteristic statistics identified initial (area under the curve = 0.753) and follow-up relative PLI volume as a predictor for ARDS (area under the curve = 0.725). CONCLUSIONS: The CT scans performed directly after admission are sufficient to define patients at risk for ARDS. Therefore, solely the incidence of PLI does not justify a routine follow-up CT scan.

Biomechanical characteristics of suture anchor implants for flexor digitorum profundus repair.

PURPOSE: To determine strength and failure characteristics of 2 suture anchors used to repair simulated flexor digitorum profundus avulsions during passive mobilization protocol simulation. METHODS: We simulated avulsion of the flexor digitorum profundus tendon in 30 distal phalanges from fresh-frozen human cadavers. Repair was performed with a 1.3 × 3.7 mm Micro-Mitek suture anchor (3-0 Orthocord suture) and a 2.2 × 4.0-mm Corkscrew suture anchor (2-0 FiberWire suture). All specimens were loaded cyclically from 2 to 15 N at 5 N/s for a total of 500 cycles. Samples were tested to failure at the completion of 500 cycles. Load at failure, load at first noteworthy displacement (> 2 mm), elongation of the system, gap formation at the tendon-bone interface, and the mechanism of failure were assessed. RESULTS: Suture failure at maximum load was the prevalent failure mechanism in both groups. No statistically significant difference in elongation of the tendon-suture complex was observed. The Corkscrew suture anchor showed a significantly superior performance in load to failure, load at first significant displacement, and gap formation at the tendon-bone interface. CONCLUSIONS: The significantly higher load capacity at first displacement (> 2 mm) and the significance of a lower gap formation at the repair site seem to be the most relevant clinical parameters. Based on this concept, the Corkscrew anchor may be superior biomechanically to the Micro-Mitek when considering an early passive mobilization protocol. CLINICAL RELEVANCE: The choice of an appropriate implant may influence the postoperative mobilization protocol and thereby improve currently reported success rates. Defining a biomechanically superior implant will provide an essential basis for further studies in flexor tendon repair research.

Improved rate of peripheral nerve regeneration induced by extracorporeal shock wave treatment in the rat.

De-focused low energy extracorporeal shock wave therapy (ESWT) has been widely used in various clinical and experimental models for the treatment of painful conditions such as epicondylitis and plantar fascitis and also bone and wound healing. There is evidence that ESWT improves the metabolic activity of various cell types, e.g. chondrocytes and endothelial cells but little is known about its effects on nervous tissue. The aim of this study was to investigate whether ESWT improves the regeneration of injured nerves in an experimental rat model. Sprague-Dawley rats received an 8mm long homotopic nerve autograft into the right sciatic nerve, fixed with epineurial sutures. Two experimental groups were set up: the group 1 animals received ESWT (300 impulses, 3 Hz) immediately after nerve grafting whereas the group 2 (control) animals received only nerve autografts. Serial CatWalk automated gait analysis, electrophysiological studies and morphological investigations were carried out. The survival time was either 3 weeks or 3 months. At 6 to 8 weeks of survival the ESWT group of animals exhibited a significantly improved functional recovery relative to the controls. Electrophysiological observations at 3 weeks after surgery revealed marked values of amplitude (3.9±0.8 mV, S.E.M.) and compound nerve action potential (CNAP, 5.9±1.4 mV·ms, S.E.M.) in the ESWT group, whereas there were no detectable amplitudes in the control group. This finding was accompanied by significantly greater numbers of myelinated nerve fibres in the middle of the graft (4644±170 [S.E.M., ESWT] vs 877±68 [S.E.M., control]) and in the distal stump (1586±157 [S.E.M., ESWT] vs 308±29 [S.E.M., control]) of ESWT animals relative to the controls 3 weeks after surgery. Three weeks after surgery the nerve grafts of control animals contained great numbers of phagocytes and unmyelinated nerve fibres, while the ESWT nerve grafts were filled with well-myelinated regenerating axons. There was no significant difference between the numbers of endoneural vessels in the ESWT and the control nerves. Three months after surgery, no significant differences were observed in the functional and electrophysiological data. Equally high numbers of myelinated axons distal to the graft could be found in both groups (7693±673 [S.E.M., ESWT] vs 6090±716 [S.E.M., control]). These results suggest that ESWT induces an improved rate of axonal regeneration, this phenomenon probably involving faster Wallerian degeneration, the improved removal of degenerated axons and a greater capacity of the injured axons to regenerate.

Epidemiological and economic aspects of polytrauma management in Austria.

INTRODUCTION: In Austria, treatment of multiple trauma patients has developed into an established nationwide trauma center specialty with its own unique identity. Although it represents a substantial financial investment, it ensures supply at international standards. The question of whether multiple trauma patients should be treated only in specialized trauma centers or in several hospitals remains controversial on both national and international grounds. The aim of this study was to assess Austrian trauma departments for international comparison. MATERIAL AND METHODS: We performed a survey of all 54 Austrian trauma departments by collecting data through questionnaires. The number of staff, potential of infrastructure, and treatment strategies were obtained. RESULTS: 93.3% of the trauma departments responded to the questionnaires. In level I trauma centers the amount of trauma beds reached 11% of the total bed capacity, 13% in level II, and 18% in level III units. Level I centers showed an average of 35% of intensive care beds for trauma patients. 53% and 51% were the proportions for level II and III centers. Level I hospitals displayed an average of 28.3 trauma surgeons, while level II and III units had less doctors at their disposal in the trauma departments. On average, 94% of the patients arrived by emergency medical support at the hospital. 94% of the trauma departments used chest tubes, 70% performed craniotomies and neurovascular reconstruction. 33% of the centers were equipped to perform replantations. DISCUSSION: The data demonstrate the broad spectrum of polytrauma treatment in Austrian trauma centers. The discussed need for centralization of polytrauma care cannot be justified based on these data. Limiting from a medical perspective, however, is the lacking comparability of quality of care due to the currently missing objective quality criteria.