Rib fractures (RF) represent the most common bone fracture after blunt trauma, occurring in 10–20% of all trauma patients and leading to concomitant injuries of the inner organs in severe cases. However, a standardized classification system for serial rib fractures (SRF) does still not exist. Basic knowledge about the facture pattern of SRF would help to predict organ damage, support forensic medical examinations, and provide data for in vitro and in silico studies regarding the thoracic stability. The purpose of our study was therefore to identify specific SRF patterns after blunt chest trauma. All SRF cases (≥3 subsequent RF) between mid-2008 and end of 2015 were extracted from the CT database of our University Hospital (n=383). Fractures were assigned to anterior, antero-lateral, lateral, postero-lateral, and posterior location within the transverse plane (36° each) using an angular measuring technique (reliability ±2°). Rib level, fracture type (transverse, oblique, multifragment, infracted), as well as degree of dislocation (none, </≥ rib width) were recorded and each related to the cause of accident. In total, 3747 RF were identified (9.7 per patient, ranging from 3 (n=25) to 33 (n=1)). On average, most RF occurred in crush/burying injuries (15.9, n=13) and pedestrian accidents (12.2, n=14), least in car/truck accidents (8.8, n=76). Altogether, RF gradually increased from rib 1 (n=140) towards rib 5 (n=517) and then decreased towards rib 12 (n=49), showing a bell-shaped distribution. More RF were detected on the left thorax (n=2027) than on the right (n=1720). Overall, most RF were found in the lateral (33%) and postero-lateral (29%) segment. Posterior RF mostly occurred in the lower thorax (63%), whereas anterior (100%), antero-lateral (87%), and lateral (63%) RF mostly appeared in the upper thorax. RF were distributed symmetrically to the sagittal plane, showing a hotspot (up to 98 RF) at rib levels 4 to 7 in the lateral segment and rib level 5 in the antero-lateral segment. In the car/truck accident group, 47% of all RF were in the lateral segment, in case of frontal collision (n=24) even 60%. Fall injuries (n=141) entailed mostly postero-lateral RF (35%). In case of falls >3 m (n=45), 48% more RF were detected on the left thorax compared to the right. CPR related SRF (n=33) showed a distinct fracture pattern, since 70% of all RF were located antero-laterally. Infractions were the most observed fracture type (44%), followed by oblique (25%) and transverse (18%) fractures, while 46% of all RF were dislocated (15% ≥ rib width). SRF show distinct fracture patterns depending on the cause of accident. Additional data should be collected to confirm our results and to establish a SRF classification system

An international Consensus Group has by a Delphi approach identified the topic of host factors affecting pin site infection to be one of the top 10 priorities in external fixator management. The aim of this study was to report the frequency of studies reporting on specific host factors as a significant association with pin site infection. Host factors to be assessed was: age, smoking, BMI and any comorbidity, diabetes, in particular. The intention was an ethological review, data was extracted if feasible, however no meta-analysis was performed. A systematic literature search was performed according to the PRISMA-guidelines. The protocol was registered before data extraction in PROSPERO. The search string was based on the PICO criterias. A logic grid with key concept and index terms was made. A search string was built assisted by a librarian. The literature search was executed in three electronic bibliographic databases, including Embase MEDLINE (1111 hits) and CINAHL (2066 hits) via Ovid and Cochrane Library CENTRAL (387 hits). Inclusion criteria: external fixation, >1 pin site infection, host factor of interest, peer-reviewed journal. Exclusion criteria: Not written in English, German, Danish, Swedish, or Norwegian, animal or cadaveric studies, location on head, neck, spine, cranium or thorax, editorials or conference abstract. The screening process was done using Covidence. A total of 3564 titles found. 3162 excluded by title and abstract screening. 140 assessed for full text eligibility. 11 studies included for data extraction. The included studies all had a retrospective design. Three identified as case-control studies. Generally the included studies was assessed to have a high risk of bias. A significant associations between pin site infection for following host factors: a) increased HbA1C level in diabetic patients; b) congestive heart failure in diabetic patients; c) less co-morbidity; d) preoperative osteomyelitis was found individually. This systematic literature search identified a surprisingly low number of studies examining for risk of pin site infection and host factors. Thus, this review most of all serves to demonstrate a gap of evidence about correlation between host factors and risk of pin site infection, and further studies are warranted

Summary Statement. We measured scapulothoracic motions during humeral abduction with different humeral rotations in healthy subjects and whole cadaver models and clarified that humeral rotation significantly influenced scapular kinematics. Introduction. Scapular dyskinesis has been observed in various shoulder disorders such as impingement syndrome or rotator cuff tears. However, the relationship between scapular kinematics and humeral positions remains unclear. We hypothesised that humeral rotation would influence scapular motions during humeral abduction and measured scapular motion relative to the thorax in the healthy subjects and whole cadavers. Methods. Healthy Subjects: Twenty-four shoulders of twelve healthy subjects without shoulder disorders were enrolled. Three electromagnetic sensors were attached on the skin over the sternum, scapula and humerus. Scapular motions during scapular plane abduction (abduction) were measured. The measurements were performed with four hand positions, palm up, thumb up, palm down and thumb down. The elbow was kept extended in all measurements. Each measurement took 5 seconds and repeated three times. Cadavers: Twelve shoulders from 6 fresh whole cadavers were used. A cadaver was set in sitting position on a wooden chair without interrupting scapular motions. Electromagnetic sensors were attached on the thorax, scapula and humerus rigidly with transcortical pins. The elbow was kept in extended position by holding the forearm and the arm was moved passively. The measurements were performed during scapular plane abduction and scapular kinematics were measured in four hand positions, 1: thumb up, 2; palm up, 3; palm down, 4; thumb down as well as the healthy subjects. Each measurement took 5 seconds and repeated three times. Data Analysis: The coordinate system and rotation angles of the thorax, scapula and humerus were decided following ISB recommendation. A one-way analysis of variance was used to test the differences in 4 arm positions. Dunnet's multiple post hoc tests were used to identify the difference between thumb up model (neutral rotation) and other three arm positions. Results. Scapular posterior tilt increased during palm up abduction (healthy subjects −2.0° to 0.1°, cadaver −3.2° to −1.4° at 120° of abduction). During thumb-down abduction, scapular posterior tilt decreased (healthy subjects −4.1° to −8.0° at 110° of abduction, cadaver −3.2° to −8.6° at 120° of abduction) and scapular upward rotation increased (healthy subjects 21.0° to 26.1° at 110° of abduction, cadaver 25.3° to 31.1° at 120° of abduction). Thumb down abduction demonstrated no significant difference from thumb up position. Discussion. Scapular motions measured in healthy subjects and cadaver models showed similar patterns indicating that surface markers on the healthy subjects could track scapular motions successfully as bone markers in cadaver models. Humeral external rotation increased scapular posterior tilt and humeral internal rotation increased scapular anterior tilt and upward rotation. This suggests that position of the greater and lesser tuberosity and tension of the joint capsule caused scapular tilt and scapular upward rotation. Kinematic changes caused by humeral rotations were observed in earlier phase of abduction in healthy subjects than in cadaver models. This suggests that healthy subjects set scapular position beforehand not to increase subacromial pressure. Conclusion. Humeral rotation significantly influenced scapular kinematics. Assessment for these patterns is important for evaluation of shoulder pathology associated with abnormal scapular kinematics

Background. The improvement of the rib cage deformity (RCD) after surgery correction has not been correlated in detail with the correction of vertebral axial rotation (AR). The loss of at the rib cage after correction has been never monitored. The hypothesis of this work was that the aesthetic improvement of RCD in adolescent idiopathic scoliosis (AIS) does not follow completely the reduction of thoracic AR after correction surgery. Moreover, lesser correction of thorax deformity could be expected in mature patients with more rigid curves. Methods. Multicenter prospective study of the modifications of the rib cage deformity in 24 patients operated because of AIS Lenke type 1A. RDC was assessed in the preoperative MRI exams including the thoracic perimeter. Vertebral AR was quantified by the RaSac angle. Anterior and posterior rib hump, and the translation of the sternum were measured in mm according to standard protocols. All these parameters were assessed in the immediate post-op period and 2-years after surgery using CT-scan axial slides. In all cases, a vertebral derotation technique performed by asymmetric rod bending was used. Immature (Risser 0–2) and mature (Risser 3–4) patients were compared. Results. Mean age of patients was 14±2 years. The preoperative curve magnitude was 56.2±8.3 Cobb degrees. RaSac at the apex was 27.2±2.8 degrees. There were 10 immature and 14 mature patients. There were no differences between the two groups in all the radiological measurements of the curves. Immature patients showed lesser posterior rib hump as compared to mature cases (14.9±4.1 mm versus 38.1±22.9; p<0.001). Postoperative vertebral AR was lesser in immature patients (2.0±1.2 versus 7.9±2.4 degrees) and increased slightly at 2-year check-up. The posterior rib hump showed also a slightly increased 2 years after surgery. In 18 cases (75%), a contralateral anterior rib hump less than 3 mm emerged after surgery that diminished but not disappeared at 2-year check-up. Conclusions. The rib cage deformity showed a lesser correction than the vertebral axial rotation. Besides this finding, immature patients showed more rib cage plasticity showing both greater modifications after surgery, and higher loss of correction during follow-up. Level of evidence. Level IV

Malpositioning of the trochanteric entry point during the introduction of an intramedullary nail may cause iatrogenic fracture or malreduction. Although the optimal point of insertion in the coronal plane has been well described, positioning in the sagittal plane is poorly defined.

The paired femora from 374 cadavers were placed both in the anatomical position and in internal rotation to neutralise femoral anteversion. A marker was placed at the apparent apex of the greater trochanter, and the lateral and anterior offsets from the axis of the femoral shaft were measured on anteroposterior and lateral photographs. Greater trochanteric morphology and trochanteric overhang were graded.

The mean anterior offset of the apex of the trochanter relative to the axis of the femoral shaft was 5.1 mm (sd 4.0) and 4.6 mm (sd 4.2) for the anatomical and neutralised positions, respectively. The mean lateral offset of the apex was 7.1 mm (sd 4.6) and 6.4 mm (sd 4.6), respectively.

Placement of the entry position at the apex of the greater trochanter in the anteroposterior view does not reliably centre an intramedullary nail in the sagittal plane. Based on our findings, the site of insertion should be about 5 mm posterior to the apex of the trochanter to allow for its anterior offset.

Cite this article: Bone Joint J 2014;96-B:1274–81.

The aim of this study was to establish a classification system for the acromioclavicular joint using cadaveric dissection and radiological analyses of both reformatted computed tomographic scans and conventional radiographs centred on the joint. This classification should be useful for planning arthroscopic procedures or introducing a needle and in prospective studies of biomechanical stresses across the joint which may be associated with the development of joint pathology.

We have demonstrated three main three-dimensional morphological groups namely flat, oblique and curved, on both cadaveric examination and radiological assessment. These groups were recognised in both the coronal and axial planes and were independent of age.