The Documentation of Injuries Caused by Traffic Accidents.

BACKGROUND: Persons injured in traffic accidents may have injuries of characteristic types that are of significance for the complex reconstruction of the accident and whose medicolegally sound clinical documentation is highly important. This is of particular relevance for the approximately 55 000 persons who are severely injured in traffic accidents in Germany each year. Gaps in documentation are often disadvantageous for the injured persons. METHODS: This review is based on pertinent publications retrieved by a selective literature review, with additional consideration of relevant textbooks in traffic medicine and legal medicine, as well as the guidelines of the AWMF (Association of the Scientific Medical Societies in Germany). RESULTS: Injuries in traffic accidents typically differ depending on the mode of participation of the injured person in traffic. They must be examined with a view toward the sequence of events of the accident and documented in medicolegally sound fashion. In particular, because of the different mechanical forces involved, it is important to document the seat that the injured person occupied in the automobile, the nature of the collision (pedestrian vs. automobile; bicycle, e-bike, e-scooter, and motorcycle accidents), and the protective devices that were in use. CONCLUSION: The precise documentation of injuries and examination findings, with critical consideration of their plausibility in relation to the sequence of events of the accident as far as it is known, is an important duty of the physician. This documentation serves as the basis for further judicial steps leading to compensation when legally appropriate.

A Comparison of Severely Injured Patients after Suicide Attempts and Violent Crimes-A Retrospective Study of a Level 1 Trauma Center.

BACKGROUND: Seriously injured persons with pre-existing psychiatric conditions or those injured due to violent crimes represent a particularly vulnerable treatment group. METHODS: All patients with injuries from suicidal attempts (PSAs) or patients with injuries from violent offenses (PVOs) that presented to the university emergency room of a Level 1 trauma center in Germany between 1 January 2017 and 31 November 2022 were retrospectively investigated. RESULTS: It can be seen that PVOs were significantly younger compared to PSAs (p = 0.03). Total hospital stay was significantly longer for PSAs compared to PVOs (p < 0.001). PSAs were also significantly more severely injured than PVOs (p < 0.001). Our study was able to show a significant difference between both patient groups in the region of injury (p < 0.001). PSAs had a significantly more extensive psychiatric history than PVOs (p < 0.001). CONCLUSION: Injuries from suicide attempts and violent offenses are a serious and growing public health problem, but one that can be addressed through timely, evidence-based, and often cost-effective interventions. It requires early interaction among multiple disciplines and a standardized approach.

Cortical Desmoid of the Distal Femur-Incidentaloma or Insertional Tendinopathy?

BACKGROUND: The cortical desmoid (DFCI) of the posteromedial femoral condyle is considered an asymptomatic incidental finding in adolescents without clinical relevance. The aim of this study was to evaluate the clinical relevance of DFCI from both a tumor orthopedic and sports medicine point of view. METHODS: n = 23 patients (13.74 ± 2.74 years; nineteen female, four male) with DFCI of the posteromedial femoral condyle were included. A localized posteromedial knee pain on exertion was differentiated from non-specific knee pain. Symptom duration, additional pathologies, number of MRIs, sports activity and training intensity, downtime, therapeutic modalities, and relief/remission of symptoms were documented. The Tegner activity scale (TAS) and Lysholm score (LS) were collected. The influence of specific posteromedial pain, MRI presence of paratendinous cysts, sports level as well as physiotherapy on downtime and LS/TAS was statistically analyzed. RESULTS: 100% reported knee symptoms at initial presentation. A localized posteromedial pain was documented in 52%. In 16/23 (70%) additional functional pathologies were diagnosed. Patients were physically highly active with high training intensities (6.52 ± 5.87 h/week) and performance level (65% competitive vs. 35% recreational). Patients underwent 1.91 ± 0.97 MRIs (max four). Symptom duration was 10.48 ± 11.02 weeks. A follow-up examination was performed after 12.62 ± 10.41 months (n = two lost to follow-up). 17/21 had physiotherapy, on average 17.06 ± 13.33 units. Overall downtime was 13.39 ± 12.50 weeks, the return-to-sports (RTS) rate 81%. 100%/38% reported a relief/remission of complaints. LS was 93.29 ± 7.95, median TAS before onset of knee complaints/at follow-up 7 (6-7)/7 (5-7). Specific posteromedial pain, presence of paratendinous cysts, sports level and physiotherapy had no significant influence on downtime and outcome parameters (n.s.). CONCLUSIONS: DFCI as a pathognomonic finding is recurrently encountered in the MRIs of children and adolescents. This knowledge is essential to spare patients from overtreatment. Contrary to the literature, the present results implicate a clinical relevance of DFCI particularly in those who are physically highly active with localized pain on exertion. Structured physiotherapy as basic treatment is recommended.

[E-scooter, e-bike and bicycle injuries in the same period-A prospective analysis of a level 1 trauma center]. / E-Scooter­, E-Bike- und Fahrradverletzungen im gleichen Zeitraum ­ eine prospektive Vergleichsstudie eines Level-1-Traumazentrums.

BACKGROUND: The actual number of accidents in e­scooter drivers in Germany seems to be significantly higher than the current figures from the Statistisches Bundesamt suggest. This epidemiological study examines e­scooter injuries and compares them with e­bike and bicycle injuries. OBJECTIVE: In order to create a comparable database on the dangers of e­scooters, e­bikes and bicycles, the typical injury patterns were analyzed and prevention options derived from them. MATERIAL AND METHODS: All accidents involving e­scooters, e­bikes and bicycles that were presented via the university emergency room of a level 1 trauma center between 15 June 2019 and 31 October 2020 were prospectively investigated. RESULTS: In our study, 68 accidents in e­scooter drivers were included, of which only 11.8% (n = 8) were recorded by the police. Significantly more of them were male than female (p = 0.032) with a mean age of 31.1 (±13) years. At the same time, we registered 34 accidents in e­bike riders and 356 in cyclists. In all three groups, most injuries occurred to the head, followed by injuries to the upper extremities. Significantly more e­scooter drivers had an ISS ≥ 16 than in the group of injured cyclists (p = 0.016). E­scooter riders who had an accident had a significantly longer length of stay in hospital, than e­bike riders (p = 0.003) and cyclists (p = 0.001), 52.9% (n = 18) of e­bike riders and 53.3% (n = 113) cyclists wore a helmet, compared to only 1.5% (n = 1) of e­scooter riders. The most common cause of accidents among e­bike riders (17.7%; n = 6) and cyclists (10.4%; n = 37) was slipping away on tram rails, while for e­scooter riders it was colliding with a curb (7.4%; n = 5). CONCLUSION: The three patient collectives examined showed different causes and profiles of injuries. The reasons for an increased proportion of seriously injured people compared to cyclists are electromobility, driving under the influence of alcohol and inadequate wearing of a helmet on e­scooters when head injuries dominate. 73.5% (n = 50) of the e­scooter accidents recorded by us were not registered by the police and therefore do not appear in the current statistics of the statistisches Bundesamt. As a result, a much higher number of e­scooter accidents can be assumed. Preventive measures could include the introduction of compulsory helmets, a higher number of traffic controls and the expansion of bike tracks.

Increased UHMWPE Particle-Induced Osteolysis in Fetuin-A-Deficient Mice.

Particle-induced osteolysis is a major cause of aseptic prosthetic loosening. Implant wear particles stimulate tissue macrophages inducing an aseptic inflammatory reaction, which ultimately results in bone loss. Fetuin-A is a key regulator of calcified matrix metabolism and an acute phase protein. We studied the influence of fetuin-A on particle-induced osteolysis in an established mouse model using fetuin-A-deficient mice. Ten fetuin-A-deficient (Ahsg−/−) mice and ten wild-type animals (Ahsg+/+) were assigned to test group receiving ultra-high molecular weight polyethylene (UHMWPE) particle implantation or to control group (sham surgery). After 14 days, bone metabolism parameters RANKL, osteoprotegerin (OPG), osteocalcin (OC), alkaline phosphatase (ALP), calcium, phosphate, and desoxypyridinoline (DPD) were examined. Bone volume was determined by microcomputed tomography (µCT); osteolytic regions and osteoclasts were histomorphometrically analyzed. After particle treatment, bone resorption was significantly increased in Ahsg−/− mice compared with corresponding Ahsg+/+ wild-type mice (p = 0.007). Eroded surface areas in Ahsg−/− mice were significantly increased (p = 0.002) compared with Ahsg+/+ mice, as well as the number of osteoclasts compared with control (p = 0.039). Fetuin-A deficiency revealed increased OPG (p = 0.002), and decreased levels of DPD (p = 0.038), OC (p = 0.036), ALP (p < 0.001), and Ca (p = 0.001) compared with wild-type animals. Under osteolytic conditions in Ahsg−/− mice, OPG was increased (p = 0.013), ALP (p = 0.015) and DPD (p = 0.012) were decreased compared with the Ahsg+/+ group. Osteolytic conditions lead to greater bone loss in fetuin-A-deficient mice compared with wild-type mice. Reduced fetuin-A serum levels may be a risk factor for particle-induced osteolysis while the protective effect of fetuin-A might be a future pathway for prophylaxis and treatment.

"The Baltic Sea Germ": A Case Report of Necrotizing Fasciitis following Vibrio vulnificus Infection.

Reported is an 80-year-old patient with septic shock from necrotizing fasciitis secondary to a Vibrio vulnificus (Vv) infection. The patient reports having been swimming in the Baltic Sea after a minor trauma to the left leg. Emergency superficial necrosectomy followed by intensive medical therapy was performed. Antibiotic therapy was initiated with a third-generation cephalosporin and a tetracycline. Vv was detected in the intraoperative microbiological smears. Instead of a leg amputation and a flap, due to the patient's age, a split skin covering to consolidate the wound was performed. Vv is a gram-negative rod bacterium of the genus Vibrio. Vv occurs in warm, low-salinity seawater (brackish water). In Germany, Vv occurs primarily in river mouths of the low-salinity Baltic Sea. Infections by Vv can occur through open wounds or by eating raw infected seafood, especially oysters. Infection via wounds often take a fulminant lethal course. Patients with chronic diseases, weakened immune system, and open wounds are particularly at risk. Infections with Vv are rare, but occur worldwide. Global warming is expected to spread Vv as water temperature increases and the dilution effect of sea level rise further decreases ocean salinity, and natural disasters promote the spread of Vv.

[Rupture of the pectoralis major muscle in amateur athletes: a rare injury or often overlooked?] / Die Ruptur des M. pectoralis major beim Hobbysportler ­ seltene Verletzung oder oft übersehen?

INTRODUCTION: A rupture of the pectoralis major muscle is a rare injury pattern overall, but it is frequently described in athletes, particularly in weightlifting. The risk of sustaining this type of injury is present especially during the eccentric phase of muscle loading. An association between such injuries and the abuse of anabolic steroids is described in the literature, but there is no coherent evidence to support this. We report the case of a young patient with a normal habitus who suffered a humeral rupture of the pectoralis major muscle during recreational sports. There was no history of excessive weight training or use of anabolic steroids. CASE HISTORY: This 33-year-old patient reported a sudden onset of left pectoral pain during training on the chest fly machine as well as a whip-like popping sound, followed by an immediate painful restriction of movement in the left arm. A clinical examination revealed a mild haematoma located on the left medial upper arm with localised tenderness and a discrete asymmetry of the contour of the pectoral muscles. Due to the typical medical history, we established the indication for surgical exploration although the clinical picture was rather discrete and only an incomplete rupture was seen in an MRI scan. Intraoperatively, we detected a complete rupture of the sternocostal part of the pectoralis major muscle with marked retraction and haematoma. Reinforcement and reinsertion were performed at the "footprint" using titanium anchors (2 x 5.5mm Corkscrew FT, Arthrex, Florida). The patient was able to resume his sports activities at the pre-traumatic level four months after surgery. CONCLUSION: A rupture of the insertion of the pectoralis major muscle must also be considered in amateur athletes with a typical history. The characteristic clinical symptoms described in the literature mostly refer to competitive athletes and bodybuilders, but these injuries can also be diagnosed in amateur athletes with lower muscle mass by subtle clinical examination. Nevertheless, there is a considerable risk of underestimating the extent of the injury. In case of doubt, surgical exploration should be performed promptly in amateur athletes. Surgical refixation of the humeral rupture of the pectoralis major muscle is the gold standard and should not be reserved to high-performance athletes.

Injuries and Overuse Injuries in Show Jumping-A Retrospective Epidemiological Cross-Sectional Study of Show Jumpers in Germany.

This retrospective cross-sectional epidemiological study deals with sport-specific injury patterns in show jumping. A total of 363 show jumpers of all levels (S) answered a retrospective questionnaire about injuries and overuse damages which occurred in the course of their careers. Demographic data and information on injuries in various body regions were collected. In addition to descriptive analysis, significance tests were performed. For better statistical comparability with other sports, exposure time was extrapolated with total career duration and weekly training hours, and injuries per 1000 jumping hours were calculated. The study included 251 (69%) women and 112 (31%) men, who were on average 26.9 ± 10.9 years old. The injury rate for the entire collective was 3.7 per 1000 h of exposure. The most frequently affected body region was the head (31%). Overuse complaints play a subordinate role and mainly affect the upper extremities (65%). The riders of the professional lower performance levels are less likely to injure themselves per 1000 h than riders of the higher performance levels. Riders who often or always wore a helmet suffered significantly fewer head injuries (p = 0.008) and had a significantly lower total injury duration than riders who did not wear a helmet (p = 0.006). Similarly, the study showed that riders who often or always wore a safety vest suffered significantly fewer spinal injuries (p = 0.017) and had significantly fewer injuries per 1000 riding hours (p = 0.031) than riders who did not wear a safety vest. Based on the present results, there should be an extension of the general helmet requirement and a requirement to wear safety vests in show jumping in general.

Injuries in underwater rugby: a retrospective cross-sectional epidemiological study.

INTRODUCTION: Underwater rugby (UWR) is a team sport which combines swimming sprints, apnoea diving, a good overview of the three-dimensional underwater space and wrestling for the ball.This was the first epidemiological study of UWR injuries in a large international collective. METHODS: A questionnaire containing 124 questions was distributed to 198 active UWR players and completed under the supervision of medical staff. Demographic data and information about injuries in ten different body regions were collected. RESULTS: Of the 198 respondents, 106 (53.5%) were male and 92 (46.5%) were female. On average, each UWR player suffered a median of 19.5 (IQR 44) injuries. Based on the exposure time, means of 37.7 (SD 90.0) injuries per 1000 playing hours per player and 9.9 (20.1) injuries per year were found. Significant injuries mainly occurred to the head region (45.7%). Bruises and sprains were observed more often than fractures and dislocations. Male athletes had a longer total injury break time (median 4.8 [IQR 10.5] days), than female athletes (4 [8.6] days). Female athletes had more injuries (median 20 [IQR 26.8]) than male athletes (18.5 [63]). The length of the injury-related break time increased with the rise in body mass index. CONCLUSIONS: The risk of severe injury in UWR is low compared to other ball sports like water polo and rugby. UWR is played under water and the impact of tackles is lessened by the water. Further studies should record chronic injuries in UWR and establish measures to prevent injury.

Geriatric Proximal Femur Fractures During the Covid-19 Pandemic - Fewer Cases, But More Comorbidities.

BACKGROUND: The COVID-19 pandemic is challenging healthcare systems worldwide. This study examines geriatric patients with proximal femur fractures during the COVID-19 pandemic, shifts in secondary disease profile, the impact of the pandemic on hospitalization and further treatment. METHODS: In a retrospective monocentric study, geriatric proximal femur fractures treated in the first six months of 2020 were analyzed and compared with the same period of 2019. Pre-traumatic status (living in a care home, under supervision of a legal guardian), type of trauma, accident mechanism, geriatric risk factors, associated comorbidities, time between hospitalization and surgery, inpatient time and post-operative further treatment of 2 groups of patients, aged 65-80 years (Group 1) and 80+ years (Group 2) were investigated. RESULTS: The total number of patients decreased (70 in 2019 vs. 58 in 2020), mostly in Group 1 (25 vs. 16) while the numbers in Group 2 remained almost constant (45 vs. 42). The percentage of patients with pre-existing neurological conditions rose in 2020. This corresponded to an increase in patients under legal supervision (29.3%) and receiving pre-traumatic care in a nursing home (14.7%). Fractures were mostly caused by minor trauma in a home environment. In 2020, total number of inpatient days for Group 2 was lower compared to Group 1 (p = 0.008). Further care differed between the years: fewer Group 1 patients were discharged to geriatric therapy (69.6% vs. 25.0%), whereas in Group 2 the number of patients discharged to a nursing home increased. CONCLUSIONS: Falling by elderly patients is correlated to geriatric comorbidities, consequently there was no change in the case numbers in this age group. Strategic measures to avoid COVID-19 infection in hospital setting could include reducing the length of hospital stays by transferring elderly patients to a nursing home as soon as possible and discharging independent, mobile patients to return home.

Acute Joint Blockage due to Abrasion-Related Dislocation of a Silastic Radial Head Prosthesis: A Histological Examination after 14 Years of Durability.

The implantation of a radial head prosthesis can take place as a therapeutic option after radial head fracture. There are various implants for this purpose. Many studies and case reports about silastic radial head prosthesis implantation describe foreign body reactions with accompanying synovitis and poor functional results. A few studies have investigated the reason for the material failure and the accompanying synovitis. The case report presented shows an unusually long durability of an in situ 14-year silastic radial head prosthesis. 14 years after implantation, a previously full-time working and healthy patient presented himself with a dislocation of the silastic radial head prosthesis and atraumatic joint blockage of the right elbow triggered by a negligible movement. The prosthesis was removed surgically. We found a macroscopic foreign body reaction intraoperatively. In a histopathological examination, with hematoxylin and eosin staining (HE) in 40x and 100x magnification, we have seen an aseptic inflammatory response to foreign bodies with activated epithelial cells and multinucleated giant cells with intracytoplasmic foreign material. Due to these problems, the silastic radial head prosthesis is no longer used today. However, there are still patients with the implanted silastic radial head prosthesis, which should therefore be checked regularly. A metal prosthesis also does not seem to be an optimal alternative due to cartilage wear and loss of ROM. The choice of prosthesis material should be selected carefully and patient-specific in radial head prosthetics according of the results presented.

A Selection of Trauma Scores Might Not Correlate with Coagulation Factor Activity following Multiple Injuries: A Retrospective Observational Study from a Level 1 Trauma Center.

Loss and dilution of coagulation factors have been observed following multiple trauma. Timely recognition of reduced clotting factor activity might facilitate therapeutic action to restore normal coagulation function. This study investigates the potential role of some well-known trauma scores in predicting coagulation factor activity after multiple injuries. A dataset comprising the coagulation factor activities of 68 multiply injured adult patients was analyzed. The following trauma scores were evaluated: AIS, ISS, NISS, GCS, RTS, TRISS, RISC, and TASH score. To investigate the effect of trauma severity with respect to a single anatomic injury location, two groups according to the AIS (<3 vs. ≥3 points) were formed. Differences between these two groups were analyzed for five different body regions (head, thorax, abdomen, pelvis, extremities) using the Mann-Whitney U-test. Spearman's rank correlation coefficient rho was calculated to reveal possible relationships between trauma scores and clotting factor activities. The analysis showed clearly reduced clotting factor activities with a significant reduction of FII (83 vs. 50%; P = .021) and FV (83 vs. 46%; P = .008) for relevant (AIS ≥ 3 points) pelvic injuries. In contrast, traumatic brain injury according to the AIS head or the GCS does not appear to lead to a significant decrease in coagulation factor activities. Furthermore, the other scores studied show at best a fair correlation with coagulation factor activity. In this context, the RTS score seems to be the most suitable. Additionally, the predictive value of the TASH score, which was specifically developed to predict the need for mass transfusion, was also limited in this study. We would like to explicitly point out that this is not a criticism of the trauma scores, since they were developed in a completely different context.

[Injuries in inline skater hockey]. / Verletzungen im Inline-Skaterhockey.

In Germany, Inline Skater Hockey (ISH) is played by about 7500 active players on inline skates with equipment comparable to ice hockey using a hard-plastic ball. The aim of this retrospective epidemiological cross-sectional study is to record the frequency and types of injuries in this sport, for which there is a lack of medically adequate studies in the literature. A questionnaire comprising 112 items was used to collect demographic data, injuries in eight body regions and defined overuse injuries. 274 ISH players with an average age of 24.5 ± 6.2 years and an exposure time of 2787 ±â€Š2063 hours were examined. 5701 injuries were recorded, 60.5 % of which were minor bruises, abrasions and wounds. The total injury rate per 1000 hours was 9.6 ±â€Š17.7, with an injury-related break of 12.8 ±â€Š21.8 weeks per player. Field players with visors had highly significantly fewer head injuries (2.8 ±â€Š6.1 vs. 8.9 ± 13.1; p < 0.001) with highly significantly (p < 0.001) fewer lacerations, nasal bone fractures, eye injuries and dental injuries. There was a weak negative correlation between facial protection and number of head injuries (r = -0.386, p < 0.001). In conclusion, frequency and types of injuries in ISH are comparable to ice hockey during training. In accordance with ice hockey, protective equipment in ISH can significantly reduce the occurrence of head injuries. Preventive attention should be paid to the wearing of a full visor and to education about the occurrence of concussions despite the use of a protective helmet.

Development of Case Numbers during the COVID-19 Pandemic in a Center of Maximum-Care for Traumatology and Orthopedic Oncology.

(1) Background: The COVID-19 pandemic has led to a significant change in the utilization of trauma surgery and tumor orthopedic hospital facilities. (2) Methods: In a monocentric retrospective analysis, the weekly numbers of cases requiring intra-clinical treatment in the first four months of 2020 were compared with those of 2019. Patients' visits to the emergency department and shock room, consultation hours, work-related accidents, case numbers in the normal and intensive care units, ventilation hours, the "Simplified Acute Physiology Score/ Therapeutic Intervention Scoring System" (SAPS/TISS), the average length of stay in hospital, the number of operations and their degree of urgency, as well as deaths, were analyzed in a study based on the data from 7606 outpatient consultations in 2019 and 6755 in 2020, as well as 993 inpatient cases in 2019 and 950 in 2020. (3) Results: There was a significant reduction in the number of treatments per week in the emergency department (261 ± 29 vs. 165 ± 25; p < 0.001) with the same number of shock room treatments and fewer consultation hour contacts (226 ± 29 vs. 119 ± 65; p = 0.012). There were fewer inpatient cases (66 ± 7 vs. 42 ± 11; p = 0.001), resulting in a fall in the days of hospitalization (492 ± 63 vs. 308 ± 78; p < 0.001) and number of operations (73 ± 7 vs. 55 ± 10; p = 0.012), especially elective procedures (20 ± 3 vs. 7 ± 7; p = 0.008). The SAPS/TISS score was lower (1351 ± 1213 vs. 399 ± 281; p = 0.023). Fewer fracture treatments and septic surgeries were performed, while the number of procedures to treat orthopedic malignancies remained constant. (4) Conclusions: During the first phase of the COVID-19 pandemic, we observed a significant reduction in the number of cases treated in orthopedics. While the number of multiple-injured patients was unchanged, fewer patients presented for primary and regular care. Treatment of acute injuries and malignant tumor diseases was not at risk. There was no effect on in-house mortality. We see a potential for the recruitment of medical staff from the outpatient department, operating room, and the ward. In the event of a future second wave, our results may allow for early planning, particularly of the all-important human resources. Reorganization by hospitals and decreased patient numbers in trauma surgery can enable the reallocation of medical staff, equipment, and beds to increase capacity for COVID-19 patients.

Lollipop Sign - Ossification at Wire Ends after Osteosynthesis?

INTRODUCTION: Heterotopic ossification (HO) is abnormal formation of new bone in the soft tissue. HO occurs outside the normal bone within soft tissues such as muscles and tendons, and histologically, it is no different from skeletal bone. It is still not clear what factors stimulate HO. The soft tissue around the hip joint has been identified as the most common location for HO. Patients with HO usually have no clinical symptoms; however, it can become very painful and lead to severe functional limitations. The standard diagnostic procedure consists of conventional X-ray diagnostics and/or skeletal scintigraphy. Local radiation and nonsteroidal anti-inflammatory drugs are the classical options for treatment and prophylaxis of HO. We describe two pediatric patients with "lollipop-like" HO at the end of Kirschner wires (K-wires, steel) and titanium elastic nails (TENs, titanium). CASE REPORT: A 9-year-old girl, 1 year after Salter and Pemberton osteotomy with K-wires, and a 15-year-old boy, 1 year after fracture of the right femur treated by osteosynthesis with TENs, were treated in our department due to HO. The girl did not report any symptoms, while the boy had pain in the location where the ossification had formed. However, examination of the girl's hip showed that the range of motion in the hip affected by HO was limited in comparison with the opposite unaffected hip. CONCLUSION: To the best of our knowledge, lollipop-like HO around protruding K-wires or TENs has not yet been described. According to literature, HO is mainly located in the pelvic region and at the elbow. Most studies investigating HO describe cases which have occurred after cemented or uncemented hip replacement surgery. In the cases presented here, HO might have been stimulated by repetitive muscle trauma above the protruding K-wire and TENs, the trauma caused by the operation, bone marrow cells dispersed intraoperatively, or by a combination of these and other factors. There are numerous studies on strategies to prevent HO after joint replacement. We suggest "lollipop sign" as a name for this rare type of HO around the end of K-wires/TENs in pediatric patients.

Wooden Penetrating Pelvic Trauma Passing the Foramen Ischiadicum.

We describe the case of a 45-year-old woman who suffered an impalement injury of the pelvis with penetration of the sciatic foramen by a wooden foreign body. Following a single operation, the injury healed without complications or infection. We have taken this as an opportunity to describe the case and our standard procedure in more detail.

Improved repair of chondral and osteochondral defects in the ovine trochlea compared with the medial condyle.

Associations between topographic location and articular cartilage repair in preclinical animal models are unknown. Based on clinical investigations, we hypothesized that lesions in the ovine femoral condyle repair better than in the trochlea. Full-thickness chondral and osteochondral defects were simultaneously established in the weightbearing area of the medial femoral condyle and the lateral trochlear facet in sheep, with chondral defects subjected to subchondral drilling. After 6 months in vivo, cartilage repair and osteoarthritis development was evaluated by macroscopic, histological, immunohistochemical, and biochemical analyses. Macroscopic and histological articular cartilage repair and type-II collagen immunoreactivity were better in the femoral trochlea, regardless of the defect type. Location-independently, osteochondral defects induced more osteoarthritic degeneration of the adjacent cartilage than drilled chondral lesions. DNA and proteoglycan contents of chondral defects were higher in the condyle, reflecting physiological topographical differences. The results indicate that topographic location dictates the structural patterns and biochemical composition of the repair tissue in sheep. These findings suggest that repair of cartilage defects at different anatomical sites of the ovine stifle joint needs to be assessed independently and that the sheep trochlea exhibits cartilage repair patterns reflective of the human medial femoral condyle.