Evaluating the stability of external fixators following pelvic injury: A systematic review of biomechanical testing methods.

INTRODUCTION: This systematic review aims to identify previously used techniques in biomechanics to assess pelvic instability following pelvic injury, focusing on external fixation constructs. METHODS: A systematic literature search was conducted to include biomechanical studies and to exclude clinical trials. RESULTS: Of an initial 4666 studies found, 38 met the inclusion criteria. 84% of the included studies were retrieved from PubMed, Scopus, and Web of Science. The studies analysed 106 postmortem specimens, 154 synthetic bones, and 103 computational models. Most specimens were male (97% synthetic, 70% postmortem specimens). Both the type of injury and the classification system employed varied across studies. About 82% of the injuries assessed were of type C. Two different fixators were tested for FFPII and type A injury, five for type B injury, and fifteen for type C injury. Large variability was observed for external fixation constructs concerning device type and configuration, pin size, and geometry. Biomechanical studies deployed various methods to assess injury displacement, deformation, stiffness, and motion. Thereby, loading protocols differed and inconsistent definitions of failure were determined. Measurement techniques applied in biomechanical test setups included strain gauges, force transducers, and motion tracking techniques. DISCUSSION AND CONCLUSION: An ideal fixation method should be safe, stable, non-obstructive, and have low complication rates. Although biomechanical testing should ensure that the load applied during testing is representative of a physiological load, a high degree of variability was found in the current literature in both the loading and measurement equipment. The lack of a standardised test design for fixation constructs in pelvic injuries across the studies challenges comparisons between them. When interpreting the results of biomechanical studies, it seems crucial to consider the limitations in cross-study comparability, with implications on their applicability to the clinical setting.

Danger zone - The spermatic cord during anterior plating of the symphysis pubis.

BACKGROUND: Distances between anatomic landmarks and anatomic structures at risk are often underestimated by surgeons. PURPOSE: The goal of the study was to evaluate the distances between anatomic landmarks and the spermatic cord in case of anterior plating of the symphysis. METHODS: A total of 25 pelves (50 hemipelves) of male embalmed cadavers were dissected. A 5-hole 3.5mm locking compression plate (Synthes GmbH) was fixed from directly anterior on the symphysis. Measurements were taken 1) distance between the tips of both pubic tubercles, 2) horizontal interval between the lateral border of the plate and the medial margin of the SC (bilateral), 3) distances between the medial border of the SC and the tip of the pubic tubercle (bilateral), 4) distances between the medial border of the SC and the lateral basis of the pubic tubercle (bilateral). RESULTS: The distance between the pubic tubercles was 60.3mm in average (SD: 5.7). The interval between the lateral border of the plate and the medial margin of the SC was on average 4.5mm (SD: 1.9) on the right and 4.7mm (SD: 2.6) on the left side. The distance between the tip of the pubic tubercle and the medial border of the SC was in average 11.2mm (SD: 2.7) on the right, and 11.0mm (SD: 2.7) on the left side. The average distance between the medial border of the SC and the lateral basis of the pubic tubercle was 8.1mm (SD: 2.4) on the right and 8.2 mm (SD: 2.4) on the left side. CONCLUSION: The SC is at risk not only during dissection but also during anterior plating of the symphysis, because of its close relation to the SC. CLINICAL RELEVANCE: Average distances between the palpable pubic tubercle and the SC are below one finger breadth (as reference).

Relation of the lumbosacral trunk to the sacro-iliac joint.

This study aims to evaluate the relation between the lumbosacral trunk (LT) and the sacro-iliac joint (SIJ). In forty anatomic specimens (hemipelves) a classical antero-lateral approach to the SIJ was performed. The SIJ was marked at the linea terminalis (reference point A). Reference point B was situated at the upper edge of the interosseous sacro-iliac ligament. The length of the SIJ (distance A to B) and the distance between point A and the ventral branch of the fourth (L4) and fifth (L5) lumbar spinal nerves at the linea terminalis were measured. The SIJ had a mean length of 58.0 mm. The ventral branch of L5 was located closer to the SIJ in very long SIJs (mean length: ≥ 6.5 cm; mean distance: 9.8 mm) compared to very short joints (≤ 5 mm; mean distance: 11.3 mm). For the ventral branch of L4, very long SIJs had a mean distance of 7 mm and very short joints an average distance of 9.7 mm between point A and the nerve branch. A safe zone of approximately 1 cm to 2 cm (anterior to posterior) is present on the sacral surface (lateral to medial) for safe fixation of plates during anterior plate stabilization of the SIJ. Pelves with a shorter dorsoventral diameter of the most superior part of the SIJ apparently give more space for inserting plates.

Definition of a Risk Zone for the Axillary Nerve Based on Superficial Landmarks.

BACKGROUND: The aim of this study was to investigate the axillary nerve's location along superficial anatomical landmarks, and to define a convenient risk zone. METHODS: A total of 123 upper extremities were evaluated. After dissection of the axillary nerve, the vertical distance between the upper border of the anterolateral edge of the acromion and the proximal border of the nerve was measured. Furthermore, the interval between the proximal border and the distal border of the axillary nerve's branches was evaluated. The interval between the distal border of the branches and the most distal part of the lateral humeral epicondyle was measured. The distance between the anterolateral edge of the acromion and the lateral humeral epicondyle was evaluated. Measurements were expressed as proportions with respect to the distance between the acromion and the lateral humeral epicondyle. RESULTS: The distance between the acromion and the proximal border of the axillary nerve's branches was at a height of 10 percent of the distance between the acromion and the lateral humeral epicondyle, starting from the acromion (90 percent when starting from the lateral humeral epicondyle). The interval between the proximal and distal margins of the axillary nerve's branches was between 10 percent and 30 to 35 percent of this interval, starting from the acromion (65 to 70 percent when starting from the lateral humeral epicondyle). CONCLUSIONS: The authors were able to locate the branches of the axillary nerve at an interval between 10 and 35 percent of the distance between the acromion and the lateral humeral epicondyle, starting from the acromion. This makes the proximal third of this distance an easily applicable risk zone during shoulder surgery.

The articular branch of the peroneal nerve to the proximal tibiofibular joint descends at a mean height of approximately 18 mm distal to the postero-lateral tip of the fibular head.

PURPOSE: The aim of the study was to evaluate the anatomical details of the articular branch of the peroneal nerve to the proximal tibiofibular joint and to project the height of its descent in relation to the fibular length. METHODS: Twenty-five lower extremities were included in the study. Following identification of the common peroneal nerve, its course was traced to its division into the deep and superficial peroneal nerve. The articular branch was identified. The postero-lateral tip of the fibular head was marked and the interval from this landmark to the diversion of the articular branch was measured. The length of the fibula, as the interval between the postero-lateral tip of the fibular head and the tip of the lateral malleolus, was evaluated. The quotient of descending point of the articular branch in relation to the individual fibular length was calculated. RESULTS: The articular branch descended either from the common peroneal nerve or the deep peroneal nerve. The descending point was located at a mean height of 18.1 mm distal to the postero-lateral tip of the fibular head. Concerning the relation to the fibular length, this was at a mean of 5.1%, starting from the same reference point. CONCLUSION: The articular branch of the common peroneal nerve was located at a mean height of 18.1 mm distal to the the postero-lateral tip of the fibular head, respectively, at a mean of 5.1% of the whole fibular length starting from the same reference point. These details represent a convenient orientation during surgical treatment of intraneural ganglia of the common peroneal nerve, which may result directly from knee trauma and indirectly from ankle sprain.

Minimally Invasive Lower Leg Fasciotomy for Chronic Exertional Compartment Syndrome-How Safe Is It? A Cadaveric Study.

BACKGROUND: Chronic exertional compartment syndrome (CECS) is a recognized clinical diagnosis in running athletes and military recruits. Minimally invasive fasciotomy techniques have become increasingly popular, but with varied results and small case numbers. Although decompression of the anterior and peroneal compartments has demonstrated a low rate of iatrogenic injury, little is known about the safety of decompressing the deep posterior compartment. PURPOSE: To evaluate the risk of iatrogenic injury when using minimally invasive techniques to decompress the anterior, peroneal, and deep posterior compartments of the lower leg. STUDY DESIGN: Descriptive laboratory study. METHODS: A total of 60 lower extremities from 30 adult cadavers were subject to fasciotomy of the anterior, peroneal, and deep posterior compartments using a minimally invasive technique. Two common variations in surgical technique were employed to decompress each compartment. Anatomical dissection was subsequently carried out to identify incomplete division of the fascia, muscle injury, neurovascular injury, and the anatomical relationship of key neurovascular structures to the incisions. RESULTS: Release of the anterior and peroneal compartments was successful in all but 2 specimens. There was no injury to the superficial peroneal nerve or any vessel in any specimen. A transverse incision crossing the anterior intermuscular septum resulted in muscle injury in 20% of the cases. Release of the deep posterior compartment was successful in all but 1 specimen when a longitudinal skin incision was used, without injury to neurovascular structures. Compared with a longitudinal incision, a transverse skin incision resulted in fewer complete releases of the deep posterior compartment and a significantly higher rate of injury to the saphenous nerve (16.7%; P = .052) and long saphenous vein (23.3%; P = .011). CONCLUSION: Minimally invasive fasciotomy of the anterior, peroneal, and deep posterior compartments using longitudinal incisions had a low rate of iatrogenic injury in a cadaveric model. Complete compartment release was achieved in 97% to 100% of specimens when employing this technique. CLINICAL RELEVANCE: Minimally invasive fasciotomy techniques for CECS have become increasingly popular with purported low recurrence rates, improved cosmesis, and faster return to sport. It is important to determine whether this technique is safe, particularly given the variable rates of neurovascular injury reported in the literature.

Morphology of the Posterior Interosseous Nerve with Regard to Entrapment Syndrome.

BACKGROUND: Posterior interosseous nerve (PIN) entrapment syndrome is a rare condition and is predisposed by anatomical factors such as narrow passages through fibrous arcades; whereas, the Arcade of Frohse (AF) is the most common entrapment point. The aim of this study was to evaluate the entrance and exit points of the PIN into the supinator in detail. MATERIALS AND METHODS: One hundred unpaired upper extremities underwent dissection. The PIN's entrance and exit points from the supinator were depicted. The distances between the tip of the radial head (RH) and the AF and the exit point of the PIN from the supinator were measured. Further, it was checked if the borders of the AF and the exit point were muscular, tendinous or a combination of these. RESULTS: The interval between the PIN's entry into the supinator and the tip of the RH was at a mean of 28.9 mm. Concerning the border of the AF, in 54 cases a muscular and in 46 specimens a tendinous version could be observed. The interval between the exit point of the PIN and the tip of the RH proved to be at a mean of 64.2 mm. Further, the exit's border was muscular in 65 specimens and tendinous in 35 cases. CONCLUSION: During surgical treatment of the PIN syndrome, it needs to be kept in mind that approximately one-third of all patients might also suffer from entrapment at the exit point of the PIN.

A guideline for placement of an infra-acetabular screw based on anatomic landmarks via an intra-pelvic approach.

BACKGROUND: Due to demographic changes, more and more fracture patterns involving anterior acetabular structures occur. The infra-acetabular screw is seen a useful tool to increase stability in fixation of the acetabular cup. However, the exact position of this screw in relation to anatomic landmarks which are intra-operatively palpable via an intra-pelvic approach has not yet been determined. METHODS: This biomorphometric experimental study references the ideal screw position of an infra-acetabular screw to anatomic landmarks palpable via an intra-pelvic approach. Therefore, we created a computer tomography-based 3D-model of 40 patients (20 women, 20 men) who received a computer tomography (CT) scan of the pelvis for any other reason than an acetabular fracture. RESULTS: The entry point of an ideal infra-acetabular was of high constancy. At mean, this point was 10.2 mm caudal and 10.4 mm medial of the ilio-pubic/ilio-pectineal eminence. This reference is independent of age, gender, or physical dimensions. However, we found gender-dependent differences for the angulation and the length of the screw. CONCLUSIONS: This study provides a comprehensive guideline to determine the ideal entry point for an infra-acetabular screw via an intra-pelvic approach. The entry point is located 10.2 mm caudal and 10.4 mm medial of the ilio-pubic/ilio-pectineal eminence. TRIAL REGISTRATION: Clinical Trial Registry University of Regensburg Z-2017-0930-1 . Registered 04. Dec 2017.

Safe zone for the posterior interosseous nerve with regard to the lateral and posterior approaches to the proximal radius.

PURPOSE: The posterior interosseous nerve (PIN) is at risk during the posterior and lateral approaches to the proximal radius. We aimed to define a safe zone for these approaches to avoid injury of the PIN and to evaluate their close and changing relationship to the nerve during forearm rotation. METHODS: The study collective consisted of 50 upper limbs. After performance of the lateral approach, the distance between the tip of the radial head and the PIN's exit point from the supinator (= distance 1) and the shortest interval between the nerve's exit to the radial margin of the ulna (= distance 2) were measured in maximum pronation and supination. Then, the dorsal approach was conducted and again distance 1 and the interval between the distal margin of the anconeus and the nerve's exit point (distance 2) were evaluated (pronation and supination). RESULTS: There were significantly shorter distances during supination in comparison to pronation. Regarding the lateral approach, distance 1 changed from a mean of 60.3 mm (supination) to 62.7 mm in pronation (p < 0.001). For the dorsal approach, distance 1 decreased significantly (p < 0.001) from 62.9 mm (pronation) to 60.2 mm (supination). CONCLUSION: Supination during the lateral and dorsal approaches to the proximal radius needs to be avoided to protect the PIN. Furthermore, the nerve appeared at an interval between 45 and 84.1 mm (lateral approach) and 47.5-93.8 mm (dorsal approach), respectively. Therefore, care must be taken at this height during extension of the approaches in a distal direction.

[Prevention of Head and Brain Injuries in Football: Is there a Need to Ban Headings?] / Prävention von Gehirnerschütterungen im Juniorenfußball ­ Ist eine Abschaffung des Kopfballspiels notwendig?

Football, the most popular sports worldwide, is associated with a high number of injuries. Head and brain injuries in football are less frequent, but may result in severe long-term damage. The mechanisms of these injuries in football are multifactorial, and the ball is rarely the main cause of a head injury. Short-term, medium-term and long-term consequences of headings in football are insufficiently examined, and there are hardly any case reports about severe episodes. Heading has been banned in US junior football since November 2015, which is understandable considering the higher risk for head injuries in popular American sports such as ice hockey or American football and people's fear associated with this risk. However, the decision to ban heading in football is not based on scientific results, and different experiences have been made in European football. Therefore, this decision should not simply be transferred to Europe. In fact, other injury prevention strategies for head injuries in junior football are necessary, such as the adaptation of ball sizes, which has already been implemented. It is not necessary to change match rules in the form of a general ban on heading in football. Further scientific studies are needed for standardisation in football worldwide.

Variations of treatment in selected proximal femur fractures among surgeons with different surgical experience--A survey at an international AO course.

INTRODUCTION: Different modalities of treatment for hip fractures have been discussed in the literature; however, practice may vary between centres. A survey was conducted on participants at an international AO course to assess the current management of pertrochanteric fractures (AO/OTA 31-A2) and displaced, non-impacted, subcapital fractures (AO/OTA 31-B3) in a 35-year-old patient and an 85-year-old patient. METHODS: Surgeons taking part in an international orthopaedic course were invited to participate in a survey and were divided into two groups: inexperienced (one-to-three years since qualification) and experienced (four or more years). A survey was conducted to assess the management modalities used for pertrochanteric fractures (AO/OTA 31-A2) and displaced, non-impacted, subcapital fractures (AO/OTA 31-B3) in a 35-year-old patient and an 85-year-old patient. RESULTS: Fifty-two surgeons participated: 18 were inexperienced and 34 were experienced. The method of operative fixation for the pertrochanteric fracture was gamma-nailing for 95% of the surgeons in the inexperienced group; in the experienced group, 56% opted for gamma-nailing and 38% for dynamic hip screw (DHS). For the displaced subcapital fracture in a 35-year-old, screw fixation was the dominant treatment option for both groups. For the displaced subcapital fracture in an 85-year-old, most of the surgeons in both groups preferred hemiarthroplasty: 59% in the inexperienced group chose cemented bipolar hemiarthroplasty and 12% uncemented, whereas 56% of the experienced group suggested cemented bipolar hemiarthroplasty and 25% uncemented. DISCUSSION: This survey shows that a variety of methods are used to treat femoral neck fractures. A prospective randomised trial has shown the DHS to be the implant of choice for pertrochanteric fractures; however, this was not considered an option in the inexperienced group of surgeons and was the treatment of choice in only 13 out of 34 experienced surgeons. There is a general consensus for femoral head-conserving surgery in young patients with displaced subcapital fractures. Replacement arthroplasty was considered in the 85-year-old with a subcapital fracture. In the inexperienced group, 10 of 17 surgeons would cement the prosthesis, as would 27 of 36 in the experienced group.

PMMA-augmented SI screw: a biomechanical analysis of stiffness and pull-out force in a matched paired human cadaveric model.

INTRODUCTION: Current literature data and clinical experience show that the number of pelvic fractures continuously rises due to the increasing elderly population. In the elderly with suspected osteoporosis additional implant augmentation with bone cement seems to be an option to avoid secondary displacement. There are no reported biomechanical data in the literature comparing the fixation strength (and anchorage) of standard and augmented SI screws so far. The purpose of this study was to assess the biomechanical performance of cement-augmented versus non-augmented SI screws in a human cadaveric pelvis model. MATERIAL AND METHODS: Six human cadaveric pelvises preserved with the method of Thiel were used in this study. Each pelvis was split to a pair of 2 hemi-pelvises, assigned to 2 different groups for instrumentation with one non-augmented or one contralateral cement-augmented SI screw, placed in the body of S1 in a randomized fashion. The osteosynthesis followed a standard procedure with 3D controlled percutaneous iliosacral screw positioning. A biomechanical setup for a quasistatic pullout test of each SI screw was used. Construct stiffness and maximum pullout force were calculated from the load-displacement curve of the machine data. Statistical evaluation was performed at a level of significance p = .05 for all statistical tests. RESULTS: Stiffness and pullout force in the augmented group (501.6 N/mm ± 123.7, 1336.8 N ± 221.1) were significantly higher than in the non-augmented one (289.7 N/mm ± 97.1, 597.7 N ± 115.5), p = .04 and p = .014, respectively. BMD influenced significantly the pullout force in all study groups. CONCLUSION: Cement augmentation significantly increased the fixation strength in iliosacral screw osteosynthesis of the sacrum in a biomechanical human cadaveric model.

Assessing postural stability in the concussed athlete: what to do, what to expect, and when.

CONTEXT: Postural stability assessment is included as part of the diagnostic and monitoring process for sports-related concussions. Particularly, the relatively simple Balance Error Scoring System (BESS) and more sophisticated force plate measures like the Sensory Organization Test (SOT) are suggested. EVIDENCE ACQUISITION: RELEVANT STUDIES WERE IDENTIFIED VIA THE FOLLOWING ELECTRONIC DATABASES: PubMed, MEDLINE, EMBASE, Web of Science, ScienceDirect, and CINAHL (1980 to July 2013). Inclusion was based on the evaluation of postural sway or balance in concussed athletes of any age or sex and investigating the reliability or validity of the included tests. STUDY DESIGN: Clinical review. LEVEL OF EVIDENCE: Level 4. RESULTS: Both the SOT and the BESS show moderate reliability, but a learning effect due to repetitive testing needs to be considered. Both tests indicate that postural stability returns to baseline by day 3 to 5 in most concussed athletes. While the BESS is a simple and valid method, it is sensitive to subjectivity in scoring and the learning effect. The SOT is very sensitive to even subtle changes in postural sway, and thus, more accurate than the BESS; however, it is a rather expensive method of balance testing. CONCLUSION: Both tests serve the purpose of monitoring balance performance in the concussed athlete; however, neither may serve as a stand-alone diagnostic or monitoring tool. STRENGTH OF RECOMMENDATION TAXONOMY: B.

Interleukin-6 as inflammatory marker referring to multiple organ dysfunction syndrome in severely injured children.

BACKGROUND: Despite the suggestion that the inflammatory response in traumatized children is functionally unique, prognostic markers predicting pediatric multiple organ failure are lacking. We intended to verify whether Interleukin-6 (IL-6) displays a pivotal role in pediatric trauma similar to adults. METHODS: Traumatized children less than 18 years of age with an Injury Severity Score >9 points and consecutive admission to the hospital's pediatric intensive care unit were included. Organ function was evaluated according to the score by Marshall et al. while IL-6 levels were measured repetitively every morning. RESULTS: 59 traumatized children were included (8.4 ± 4.4 years; 57.6% male gender). Incidence of MODS was 11.9%. No differences were found referring to age, gender, injury distribution or overall injury severity between children with and without MODS. Increased IL-6 levels during hospital admission were associated with injury severity (Spearman correlation: r = 0.522, p < 0.001), while an inconsistent association towards the development of MODS was proven at that time point (Spearman correlation: r = 0.180, p = 0.231; Pearson's correlation: r = 0.297, p = 0.045). However, increased IL-6 levels during the first two days were no longer associated with the injury severity but a significant correlation to MODS was measured. CONCLUSIONS: The presented prospective study is the first providing evidence for a correlation of IL-6 levels with injury severity and the incidence of MODS in traumatized children.

The incidence of concussion in professional and collegiate ice hockey: are we making progress? A systematic review of the literature.

BACKGROUND: The fast, random nature and characteristics of ice hockey make injury prevention a challenge as high-velocity impacts with players, sticks and boards occur and may result in a variety of injuries, including concussion. METHODS: Five online databases (January 1970 and May 2012) were systematically searched followed by a manual search of retrieved papers. RESULTS: Seventeen studies met the inclusion criteria. The heterogeneous diagnostic procedures and criteria for concussion prevented a pooling of data. When comparing the injury data of European and North American or Canadian leagues, the latter show a higher percentage of concussions in relation to the overall number of injuries (2-7% compared with 5.3-18.6%). The incidence ranged from 0.2/1000 to 6.5/1000 game-hours, 0.72/1000 to 1.81/1000 athlete-exposures and was estimated at 0.1/1000 practice-hours. DISCUSSION AND CONCLUSIONS: The included studies indicate a high incidence of concussion in professional and collegiate ice hockey. Despite all efforts there is no conclusive evidence that rule changes or other measures lead to a decrease in the actual incidence of concussions over the last few decades. This review supports the need for standardisation of the diagnostic criteria and reporting protocols for concussion to allow interstudy comparisons in the future.

Predictors of poor outcome after both column acetabular fractures: a 30-year retrospective cohort study.

BACKGROUND AND PURPOSE: Acetabular fractures are often combined with associated injuries to the hip joint. Some of these associated injuries seem to be responsible for poor long-term results and these injuries seem to affect the outcome independent of the quality of the acetabular reduction. The aim of our study was to analyze the outcome of both column acetabular fractures and the influence of osseous cofactors such as initial fracture displacement, hip dislocation, femoral head lesions and injuries of the acetabular joint surface. METHODS: A retrospective cohort study in patients with both column acetabular fractures treated over a 30 year period was performed. Patients with a follow-up of more than two years were invited for a clinical and radiological examination. Displacement was analyzed on initial and postoperative radiographs. Contusion and impaction of the femoral head was grouped. Injuries of the acetabular joint surface consisting of impaction, contusion and comminution were recorded. The Merle d'Aubigné Score was documented and radiographs were analysed for arthritis (Helfet classification), femoral head avascular necrosis (Ficat/Arlet classification) and heterotopic ossifications (Brooker classification). RESULTS: 115 patients were included in the follow up examination. Anatomic reduction (malreduction ≤ 1mm) was associated with a significantly better clinical outcome than nonanatomical reduction (p = 0.001). Initial displacement of more than 10mm (p = 0.031) and initial intraarticular fragments (p = 0.041) were associated with worse outcome. Other associated injuries, such as the presence of a femoral head dislocation, femoral head injuries and injuries to the acetabular joint surface showed no significant difference in outcome individually, but in fractures with more than two associated local injuries the risk for joint degeneration was significant higher (p < 0.001) than in cases with less than two of them.In the subgroup of anatomically reconstructed fractures no significant influence of the analyzed cofactors could be observed. CONCLUSION: Anatomical reduction appears to be an important parameter for a good clinical outcome in patients with both column acetabular fractures. Additional fracture characteristics such as the initial displacement and intraarticular fragments seem to influence the results. Patients should also be advised that both column acetabular fractures with more than two additional associated factors have a significantly higher risk of joint degeneration.

Fractures of the pelvis in children: a review of the literature.

Trauma is the leading cause of death in children. Pelvic ring injuries account for 0.3-4% of all paediatric injuries. The pattern of fractures differs to that seen in adults as it is more ductile. Pelvic ring injuries tend to be more stable as the relatively thick periosteum restricts bony displacement. Intrapelvic viscera are not well protected and can sustain injury in the absence of pelvic fractures. These injuries have traditionally been treated non-operatively. In this paper, we comprehensively review the literature and propose a protocol for treatment taking into consideration associated organ injuries, hemodynamic status of the patient, patient's age, type of fracture and the stability of the pelvic ring.

Radiological landmarks for the safe extra-capsular placement of supra-acetabular half pins for external fixation.

PURPOSE: Low anterior external fixators are constructed by placing half pins in the dense bone tunnel of the supra-acetabular region in an anterior to posterior direction. Although the placement of these pins is extra-articular, they may still breach the hip capsule on the anterior inferior iliac spine and thus be intra-capsular. We aim to provide radiological markers for the most superior fibres of the capsule to allow safe extra-capsular pin placement within the supra-acetabular bone tunnel. METHODS: Thirteen cadaveric pelves were used for this study. The supra-acetabular bone tunnel was visualised with an image intensifier. The proximal most fibres of the hip joint capsule were marked with a K-wire so that their relation to the bone tunnel could be clearly seen on the images. Once all images were acquired they were calibrated and analysed to estimate the dimensions of the supra-acetabular bone tunnel and the reflection of the hip capsule. RESULTS: The median height of the bone tunnel was 23.6 mm (18.9-33.2) and maximum width was 11.4 mm (7.6-16.3). The inferior margin of the bone tunnel was 6.7 mm (1.1-14.5) superior to the acetabular dome, and the most proximal fibres of the capsule were 9.3 mm (4.7-6.1) superior to the acetabular dome. The inferior portion of the tunnel was 3.7 mm (0.3-8.9) within the joint. CONCLUSION: Half pins for the construction of a pelvic external fixator should be placed in the upper half of the supra-acetabular bone corridor to minimise the risk of intra-capsular placement.

Survival trends and predictors of mortality in severe pelvic trauma: estimates from the German Pelvic Trauma Registry Initiative.

STUDY OBJECTIVE: To determine longitudinal trends in mortality, and the contribution of specific injury characteristics and treatment modalities to the risk of a fatal outcome after severe and complex pelvic trauma. METHODS: We studied 5048 patients with pelvic ring fractures enrolled in the German Pelvic Trauma Registry Initiative between 1991 and 1993, 1998 and 2000, and 2004 and 2006. Complete datasets were available for 5014 cases, including 508 complex injuries, defined as unstable fractures with severe peri-pelvic soft tissue and organ laceration. Multivariable mixed-effects logistic regression analysis was employed to evaluate the impact of demographic, injury- and treatment-associated variables on all-cause in-hospital mortality. RESULTS: All-cause in-hospital mortality declined from 8% (39/466) in 1991 to 5% (33/638) in 2006. Controlling for age, Injury Severity Score, pelvic vessel injury, the need for emergency laparotomy, and application of a pelvic clamp, the odds ratio (OR) per annum was 0.94 (95% confidence interval [CI] 0.91-0.96). However, the risk of death did not decrease significantly in patients with complex injuries (OR 0.98, 95% CI 0.93-1.03). Raw mortality associated with this type of injury was 18% (95% CI 9-32%) in 2006. CONCLUSION: In contrast to an overall decline in trauma mortality, complex pelvic ring injuries remain associated with a significant risk of death. Awareness of this potentially life-threatening condition should be increased amongst trauma care professionals, and early management protocols need to be implemented to improve the survival prognosis.

[Internal fixation of acetabular both-column fractures via the ilioinguinal approach]. / Osteosynthese von Zwei-Pfeiler-Frakturen des Azetabulums über den ilioinguinalen Zugang.

OBJECTIVE: Open anatomic reduction and stable internal fixation of both-column acetabular fractures by screw and plate osteosynthesis via the ilioinguinal approach. INDICATIONS: Displaced both-column fractures of the acetabulum with incongruence of the hip joint, central femoral head displacement, unstable hip joint, and/or loss of hip joint congruence without the potential of a secondary congruence (near anatomic fragment orientation due to ligamentotaxis). CONTRAINDICATIONS: General contraindications. Displaced fracture of the posterior wall. Extension of the posterior column fracture to the apex of the greater sciatic notch. SURGICAL TECHNIQUE: Indirect open reduction of a both-column fracture of the acetabulum that is typically characterized by a multifragmentary anterior column fracture and a simple posterior column fragment using an ilioinguinal approach. Stepwise reduction and reconstruction of the anterior column according to the "proximal-to-distal" rule. Reduction and fixation of the posterior column fragment against the reconstructed anterior column. POSTOPERATIVE MANAGEMENT: Partial weight bearing for 8-12 weeks with 15 kg body weight, beginning on the 2nd postoperative day. Thereafter, pain-dependent weight bearing. Thrombosis prophylaxis. RESULTS: Analysis of 27 patients treated between 1991 and 2005. A high-velocity trauma was the cause of injury in 74.1% of cases. Most patients showed an isolated injury of the acetabulum. In 55.5%, an additional central hip joint displacement was observed. A primary injury to the sciatic nerve was present in 14.8% of cases. Mean fracture gap/step was 14.3 mm. 81.5% of these fractures were anatomically reduced and stabilized; all joints were congruent. At 2-year follow-up, 14 out of 17 patients had no signs of posttraumatic osteoarthritis. Excellent and good functional results according to the Merle d'Aubigné Score were observed in eleven and five cases, respectively. One patient had a moderate functional outcome.