Analysis of postoperative complications 5 years after osteosynthesis of patella fractures-a retrospective, multicenter cohort study.

PURPOSE: The study aims to investigate the influence of patient- and fracture-specific factors on the occurrence of complications after osteosynthesis of patella fractures and to compare knee joint function, activity, and subjective pain levels after a regular postoperative course and after complications in the medium term. METHODS: This retrospective, multicenter cohort study examined patients who received surgery for patella fracture at level 1 trauma centers between 2013 and 2018. Patient demographics and fracture-specific variables were evaluated. Final follow-up assessments included patient-reported pain scores (NRS), subjective activity and knee function scores (Tegner Activity Scale, Lysholm score, IKDC score), complications, and revisions. RESULTS: A total of 243 patients with a mean follow-up of 63.4 ± 21.3 months were included. Among them, 66.9% of patients underwent tension band wiring (TBW), 19.0% received locking plate osteosynthesis (LPO), and 14.1% underwent screw osteosynthesis (SO). A total of 38 patients (15.6%) experienced complications (TBW: 16.7%; LPO: 15.2%; SO: 11.8%). Implant-related complications of atraumatic fragment dislocation and material insufficiency/dislocation, accounted for 50% of all complications, were significantly more common after TBW than LPO (p = 0.015). No patient-specific factor was identified as a general cause for increased complications. Overall, particularly following complications such as limited range of motion or traumatic refracture, functional knee scores were significantly lower and pain levels were significantly higher at the final follow-up when a complication occurred. Implant-related complications, however, achieved functional scores comparable to a regular postoperative course without complications after revision surgery. CONCLUSION: The present study demonstrated that implant-related complications occurred significantly more often after TBW compared to LPO. The complication rates were similar in all groups.

S2k Guideline for Tibial Plateau Fractures - Classification, Diagnosis, and Treatment. / S2k-Leitlinie Tibiakopffraktur ­ Klassifikation, Diagnostik und Therapie.

Tibial plateau fractures are mostly complex and surgically demanding joint fractures, which require a comprehensive understanding of the fracture morphology, ligamentous and neurovascular injuries, as well as the diagnostic and therapeutic options for an optimal clinical outcome. Therefore, a standardised and structured approach is required. The success of the treatment of tibial plateau fractures relies on the interdisciplinary cooperation between surgical and conservative physicians in an outpatient and inpatient setting, physical therapists, patients and service providers (health insurance companies, statutory accident insurance, pension providers). On behalf of the German Society for Orthopaedics and Trauma Surgery (DGOU), the German Trauma Society (DGU) and the Society for Arthroscopy and Joint Surgery (AGA), under the leadership of the Fracture Committee of the German Knee Society (DKG), a guideline for tibial plateau fractures was created, which was developed in several voting rounds as part of a Delphi process. Based on the current literature, this guideline is intended to make clear recommendations and outline the most important treatment steps in diagnostics, therapy and follow-up treatment. Additionally, 25 statements were revised by the authors in several survey rounds using the Likert scale in order to reach a final consensus.

Injury Epidemiology of 626 Athletes in Surfing, Wind Surfing and Kite Surfing.

INTRODUCTION/BACKGROUND: Surfing, wind surfing and kite surfing enjoy a growing popularity with a large number of athletes worldwide. The aim of this study was to identify and compare the injury profiles and compare the injury profiles of these three extreme water sports. MATERIALS AND METHODS: These data for this retrospective cohort study were collected through an online standardised questionnaire during the 2017-18 season. The questionnaire included questions about anthropometry, skill level, injury diagnosis, injury mechanism, environmental conditions and training regimes. RESULTS: The 626 athletes included reported 2584 injuries. On average, each athlete sustained 4.12 injuries during the season. The most frequent injury location was in the lower extremity, in particular the foot, with 49 (16.4%) injuries in surfing, 344 (18.3%) in wind surfing and 79 (19.7%) in kite surfing. Surfing demonstrated a particularly high rate of head injuries (n = 37; 12.4%). Other frequent injury types were skin lesions (up to 42.1%) and contusions (up to 40.5%). The most common injury across all surfing sports was skin lesions of the foot (wind surfing: 11.7%; kite surfing: 13.2%; surfing: 12.7%). In surfing, skin lesions of the head were frequently observed (n = 24; 8.0%). In surfing, a 'too large wave' (n = 18; 24.7%) was main cause of the injury, while in wind surfing (n = 189; 34.5%) and kite surfing (n = 65; 36.7%) 'own incompetence' led to the most injuries. CONCLUSION: This unique study compares injury epidemiology and mechanism in the three most popular surfing sports: wind surfing, kite surfing and surfing. Overall, injuries were sustained mainly in the lower extremity, while surfing also demonstrated a high rate of head injuries.

Collision with opponents-but not foul play-dominates injury mechanism in professional men's basketball.

BACKGROUND: To identify injury patterns and mechanisms in professional men's basketball by means of video match analysis. METHODS: In Germany, injuries are registered with the statutory accident insurance for professional athletes (VBG) by clubs or club physicians as part of occupational accident reporting. Moderate and severe injuries (absence of > 7 days) sustained during basketball competition in one of four seasons (2014-2017 and 2018-2019) in the first or second national men's league in Germany were prospectively analyzed using a newly developed standardized observation form. Season 2017-2018 was excluded because of missing video material. RESULTS: Video analysis included 175 (53%) of 329 moderate and severe match injuries. Contact patterns categorized according to the different body sites yielded eight groups of typical injury patterns: one each for the head, shoulders, and ankles, two for the thighs, and three for the knees. Injuries to the head (92%), ankles (76%), shoulders (70%), knees (47%), and thighs (32%) were mainly caused by direct contact. The injury proportion of foul play was 19%. Most injuries (61%) occurred in the central zone below the basket. More injuries occurred during the second (OR 1.8, p = 0.018) and fourth quarter (OR 1.8, p = 0.022) than during the first and third quarter of the match. CONCLUSION: The eight identified injury patterns differed substantially in their mechanisms. Moderate and severe match injuries to the head, shoulders, knees, and ankles were mainly caused by collision with opponents and teammates. Thus, stricter rule enforcement is unlikely to facilitate safer match play.

[Extended medical preparticipation screening as a useful option for injury prevention in professional sports]. / Erweiterte medizinische Eingangsuntersuchungen als sinnvolle Instrumentarien zur Verletzungsprävention im Hochleistungssport am Beispiel eines Basketball-Bundesligisten.

BACKGROUND: Preparticipation screening is important in order to make a statement about an athlete's health. The evaluation includes both an internal medicine/cardiology and an orthopaedic section. In professional team sports, players have to undergo medical screening on an annual basis to obtain their license and be cleared for play. Screening delivers information about the acute health condition of the athlete but only gives an indirect statement on his/her functional status and performance. This gap has been tried to be closed with functional, sports-specific performance testing in the past few years. In the event of future injury, the collected data can be used as a baseline level to monitor the progress in an athlete's rehabilitation process. This provides a huge advantage in the return-to-play diagnosis. MATERIAL & METHODS: Based on the assumption that only a healthy player can perform to the best of his or her ability, we have extended our medical screening for a professional basketball team. Since the 2012/2013 season, a test battery was added with a view to basketball-specific conditioning. The collected data was prospectively correlated to injury occurrence. RESULTS: Seventy-one players were tested in 5 different categories. We have documented 142 injuries which lead to a downtime of 23 days (range 1-347 days). The injuries mainly involved the lower extremity, in particular the ankle, the knee and the thigh muscles. There was a clear trend indicating that players performing weaker in the agility tests sustained more injuries (r = 0.34, p = 0.029). Athletes who performed worse in the Yo-Yo test suffered from significantly more thigh muscle injuries (r = 0.266, p = 0.012). CONCLUSION: Pre-participation screening is a useful tool in injury prevention, which helps to detect injuries or chronic stress complaints, especially in, but not limited to professional sports. Adding sports-specific performance testing may reveal potential deficits in agility and endurance which could lead to an increased injury risk. In addition, it allows to obtain baseline data which could be used to show the progress in rehabilitation in the event of an injury.

Indoor Bouldering-A Prospective Injury Evaluation.

INTRODUCTION: Bouldering has become a sport of growing interest, but little prospective evidence exists about injury proportions and patterns. The purpose of this study was to prospectively evaluate the cause of injuries sustained during indoor bouldering, proportion of affected body location, and injury severity. METHODS: Proportions and patterns of injury among German-speaking indoor boulderers were evaluated prospectively in an explorative cohort study. Participants completed a baseline questionnaire assessing anthropometric data and sport-specific potential preventive and risk factors, followed by monthly injury questionnaires including injury location and injury severity over a period of 12 mo. RESULTS: Out of 507 boulderers, 222 (44%) sustained 305 injuries. Of those, 78% (n=238) were classified as Union Internationale de Associations d'Alpinisme (UIAA) 1, 19% (n=57) as UIAA 2, and 3% (n=10) as UIAA 3. Injuries of the upper extremities accounted for 63% (n=191) of all injuries. Injuries of the lower extremities accounted for 23% (n=71) but were more often classified as UIAA≥2 (P=0.0071; odds ratio [OR] 2.23; 95% CI 1.23-4.04) and were more often caused by falling (P=0.0005; OR 2.92; 95% CI 1.57-5.42) and jumping off the wall (P<0.0001; OR 4.39; 95% CI 2.25-8.56) than injuries of other body locations. There was no statistically significant protective effect of the evaluated potential preventive measures. Participants who used heavily downturned climbing shoes had a higher risk of sustaining a UIAA ≥2 injury (P=0.0034; OR 2.58; 95% CI 1.34-4.95). CONCLUSIONS: Injuries in indoor bouldering are common. Lower extremity injuries are associated with higher injury severity. Preventive measures need to be established to reduce bouldering injuries, especially during falls and landings.

Injury epidemiology in men's professional team sports: is media analysis helpful?

INTRODUCTION: Epidemiological injury surveillance in professional sports is often based on online media analysis in order to collect necessary data. However, the validation of this study protocol is lacking. Therefore, this study aimed to identify the validity of injury surveillance in men's professional team sports based on media reports. METHODS: In a retrospective cohort study, the validity of media-data-relating injuries was investigated in participating teams of the highest two German divisions in men's professional basketball (BB) and handball (HB) in the season 2018/2019. Injury protocols completed by the team physicians were compared to those of sports media injury reports. RESULTS: The study population was composed of 133 athletes (54 BB and 79 HB). Of 343 injuries reported by the team physicians, 151 (44%) could be identified by means of sports media reports. Severe injuries (n = 75, 72%) were reported more likely in sports media compared to less severe injuries (n = 76, 32%, p < 0.00001). Odds ratio (OR) was 5.33 (95% CI 3.22-8.82). No differences regarding injury reporting could be seen between the two team sports. CONCLUSION: For severe injuries, media analysis may be a sufficient method for data collection in popular men's professional ball sports. An underestimation of true injury prevalence lies within the range of previous reported investigations concerning the validation of injury surveillance methods. Non-severe injuries could not be verified via media analysis in professional handball and basketball.

Traumatic injuries to the hand and wrist in youth elite handball are most frequently localised to the thumb and proximal interphalangeal joints.

INTRODUCTION: Hand and wrist injuries have been described as the second most common severe injuries in handball. However, no evidence exists regarding the specific characteristics of these injuries. The aim of this study was to determine the injury pattern of hand and wrist injuries in youth handball. MATERIALS AND METHODS: Two-hundred and ninety-six adolescent elite handball players (mean age: 14.0 ±â€Š0.8 years) completed a retrospective survey regarding their hand and wrist injuries during the previous season. The injury questionnaire was adapted from sports-specific questionnaires to the demands of hand and wrist injuries in handball and included injury location, type of injury and injury severity. RESULTS: One-hundred and twenty-three (42 %) players reported 156 injuries (0.53 injuries per season per player) to their hands or wrists in the past season. Injuries to the proximal interphalangeal joints were most frequently described (n = 74, 47 %). The thumb was involved in 46 (29 %) cases. Sprains (n = 113, 72 %) were the most common type of injury. Thirty-six percent of moderate and severe injuries (> 7 days time loss) had not been treated by a physician. CONCLUSIONS: The rates of hand and wrist injuries are high in youth elite handball. Injury prevention strategies and return to competition criteria should focus on the thumb and the interphalangeal joints. Further research into these injuries is essential to identify risk factors and to develop adequate injury prevention measures.

Increased posterior shoulder capsule thickness in youth elite handball players: a sonographic investigation.

PURPOSE: Range of motion adaptations in the shoulders of overhead throwing athletes have been reported, but knowledge about the development of soft-tissue adaptations is limited. The purpose of this study was to investigate differences in posterior shoulder capsule thickness and internal rotation between the throwing and non-throwing shoulder. METHODS: On the basis of the sample size calculation, we assessed 63 youth elite handball players (33 boys and 30 girls, mean age: 13.6 ± 0.9 years) for glenohumeral internal and external rotational range of motion, humeral retrotorsion, and posterior capsule thickness (PCT) with a manual goniometer and a portable ultrasound device and calculated sports-specific differences between the throwing and non-throwing shoulder as well as correlations with PCT. RESULTS: Youth handball players showed side-to-side differences in internal rotation, external rotation, and humeral retrotorsion between the throwing and non-throwing shoulder. Posterior shoulder capsules were 1.21 times thicker (95% confidence interval: 1.1-1.3) in the throwing shoulder than in the non-throwing shoulder (1.3 ± 0.3 mm vs. 1.2 ± 0.2 mm, P < .0001). Loss of internal rotation did not correlate with PCT. CONCLUSIONS: In youth elite handball athletes, posterior shoulder tightness and subsequent sports-specific loss of internal rotation in the throwing shoulder are not related to PCT. Thus, in this age class, other (soft-tissue) factors must be responsible for this condition.

[Current treatment standard for patella fractures in Germany]. / Aktueller Versorgungsstandard von Patellafrakturen in Deutschland.

BACKGROUND: The treatment of patella fractures is technically demanding. Although the radiological results are mostly satisfactory, this often does not correspond to the subjective assessment of the patients. The classical treatment with tension band wiring with K­wires has several complications. Fixed-angle plate osteosynthesis seems to be biomechanically advantageous. OBJECTIVE: Who is treating patella fractures in Germany? What is the current standard of treatment? Have modern forms of osteosynthesis become established? What are the most important complications? MATERIAL AND METHODS: The members of the German Society for Orthopedics and Trauma Surgery and the German Knee Society were asked to participate in an online survey. RESULTS: A total of 511 completed questionnaires were evaluated. Most of the respondents are specialized in trauma surgery (51.5%), have many years of professional experience and work in trauma centers. Of the surgeons 50% treat ≤5 patella fractures annually. In almost 40% of the cases preoperative imaging is supplemented by computed tomography. The classical tension band wiring with K­wires is still the preferred form of osteosynthesis for all types of fractures (transverse fractures 52%, comminuted fractures 40%). In the case of comminuted fractures 30% of the surgeons choose fixed-angle plate osteosynthesis. If the inferior pole is involved a McLaughlin cerclage is used for additional protection in 60% of the cases. DISCUSSION: The standard of care for patella fractures in Germany largely corresponds to the updated S2e guidelines. Tension band wiring is still the treatment of choice. Further (long-term) clinical studies are needed to verify the advantages of fixed-angle plates.

Bone metabolism is a key factor for clinical outcome of tibial plateau fractures.

PURPOSE: Given that tibial plateau fractures (TPF) are rare, they may pose a challenge to the treating surgeon due to their variety of complex fracture patterns. Numerous studies have identified potential fracture-specific, surgery-related, and patient-related risk factors for impaired patient outcomes. However, reports on the influence of bone metabolism on functional outcomes are missing. METHODS: In a retrospective multicenter cohort study, 122 TPF of 121 patients were analyzed with respect to radiological and clinical outcomes (Rasmussen) with a mean follow-up of 35.7 ± 24.9 months. The risk factor assessment included bone metabolism-affecting comorbidities and medication. RESULTS: The findings showed that 95.9% of the patients reported a good-to-excellent clinical outcome, and 97.4% reported a good-to-excellent radiological outcome. Logistic regression revealed that potentially impaired bone metabolism (IBM) was an independent risk factor for the clinical (p = 0.016) but not the radiological outcome (Table 4). Patients with 41-type B fractures and a potential IBM had a seven times higher risk to present a fair-to-poor clinical outcome [OR 7.45, 95 CI (4.30, 12.92)]. The most common objective impairment was a limited range of motion in 16.4% of the patients, especially in 41-type C fractures (p = 0.06). The individual failure analysis additionally identified surgery-related options for improvement. CONCLUSION: This study demonstrated that potential IBM was an independent risk factor for a poor-to-fair clinical outcome.

[Ligamentous ankle injury: an underestimated trauma?] / Die Bandverletzung des oberen Sprunggelenks ­ eine unterschätzte Verletzung?

Ligamentous injuries of the ankle joint are among the most common injuries in sports, with landing on the opponent's foot or direct contact counting among the most common injury mechanisms. Initial measures most notably include a clinical examination, supplemented by X-rays, sonography or MRI as required. In most cases, conservative treatment is the treatment of choice. At the beginning, pain and swelling have to be reduced. Then function must be regained before patients may return to sports after a return-to-play test. Some injury patterns are more complex with concomitant injuries, and despite all the success of conservative treatment, certain cases remain the preserve of surgery. Not only the downtime of athletes, the severity of long-term damage and chronic functional limitations, but also the associated costs for treatment suggest the recommendation that ankle joint injuries should not be underestimated and adequate treatment should be selected.

Energetic Profiles of the Yo-Yo Intermittent Recovery Tests 1 and 2.

PURPOSE: To analyze the energetic profiles of the Yo-Yo Intermittent Recovery Tests 1 and 2 (YYIR1 and YYIR2). METHODS: Intermittent running distance (IR1D and IR2D), time to exhaustion (IR1T and IR2T), and total recovery time between shuttles (IR1R and IR2R) were measured in 10 well-trained male athletes (age 24.4 [2.0] y, height 182 [1] cm, weight 75.8 [7.9] kg). Respiratory gases and blood lactate (BLC) were obtained preexercise, during exercise, and until 15 min postexercise. Metabolic energy, average metabolic power , and energy share (percentage of aerobic [WAER], anaerobic lactic [WBLC], and anaerobic alactic energy system [WPCr]) were calculated using the PCr-La-O2 method. RESULTS: Peak oxygen consumption was possibly higher in YYIR2 (60.3 [5.1] mL·kg-1·min-1) than in YYIR1 (P = .116, 57.7 [4.5] mL·kg-1·min-1, d = -0.58). IR1D, IR1T, and IR1R were very likely higher than IR2D, IR2T, and IR2R, respectively (P < .001, 1876 [391] vs 672 [132] m, d = -2.83; P < .001, 916 [175] vs 304 [57] s, d = -3.03; and P < .001, 460 [100] vs 150 [40] s, d = -2.83). Metabolic energy was most likely lower in YYIR2 than in YYIR1 (P < .001, 493.5 [118.1] vs 984.8 [171.7] kJ, d = 3.24). Average metabolic power was most likely higher in YYIR2 than in YYIR1 (P < .001, 21.5 [1.7] vs 14.5 [2.2] W·kg-1, d = 3.54). When considering aerobic phosphocreatine restoration during breaks between shuttles, WAER (P = .693, 49% [10%] vs 48% [5%], d = -0.16) was similar, WPCr (P = .165, 47% [11%] vs 42% [6%], d = -0.54) possibly higher, and WBLC (P < .001, 4% [1%] vs 10% [3%], d = 1.95) almost certainly lower in YYIR1 than in YYIR2. CONCLUSIONS: WAER and WPCr are predominant in YYIR1 and YYIR2 with almost identical WAER. Higher IR1D and IR1T in YYIR1 result in higher metabolic energy but lower average metabolic power and slightly lower peak oxygen consumption. Higher IR1R allows for higher reliance on WPCr in YYIR1, while YYIR2 requires a higher fraction of WBLC.

A rare case of Hoffa fracture combined with lateral patellar dislocation.

The coronal unicondylar fracture of the distal femur (AO 33-B3) is a rare intraarticular injury within the weight bearing area of the knee, initially described by Albert Hoffa in 1904. We report an unusual combination of a Hoffa fracture with lateral patellar dislocation in a young adult. Our patient sustained the injury by a sudden twist of his leg during sports. He presented clinically with knee swelling, dislocation of the patella, and localized tenderness; unable to bare weight. After plane radiograph confirmed the injury, manual reduction of the patella was done by hyperextension of the knee and medialward pressure. Afterwards, a CT scan and MRI were conducted. The injury was surgically treated with lag-screws, locking-plate and MPFL-reconstruction.

Intra-articular tibial plateau fracture characteristics according to the "Ten segment classification".

BACKGROUND: Currently existing classifications of tibial plateau fractures do not help to guide surgical strategy. Recently, a segment-based mapping of the tibial plateau has been introduced in order to address fractures with a fracture-specific surgical approach. The goal of the present study was to analyze incidence and fracture specifics according to a new 10-segment classification of the tibial plateau. METHODS: A total of 242 patients with 246 affected knees were included (124 females, 118 males, mean age 51.9±16.1years). Fractures were classified according to the OTA/AO classification. Fracture pattern was analyzed with respect to a 10-segment classification based on CT imaging of the proximal tibial plateau 3cm below the articular surface. RESULTS: 161 Patients suffered an OTA/AO type 41-B and 85 patients an OTA/AO type 41-C tibial plateau fracture. Females had an almost seven times higher risk to suffer a fracture due to low-energy trauma (OR 6.91, 95% CI (3.52, 13.54), p<0.001) than males. In 34% of the patients with affection of the medial tibial plateau, a fracture comminution, primarily due to low-energy trauma (p<0.001), was observed. In type B fractures, the postero-latero-lateral (65.2%), the antero-latero-lateral (64.6%) and the antero-latero-central (60.9%) segment were most frequently affected. Every second type C fracture showed an unique fracture line and zone of comminution. The tibial spine was typically involved (89.4%). A typical fracture pattern of high-energy trauma demonstrated a zone of comminution of the lateral plateau and a split fracture in the medial plateau. The most frequently affected segments were the postero-latero-central (85.9%), postero-central (84.7%), and antero-latero-central (78.8%) segment. CONCLUSION: Posterior segments were the most frequently affected in OTA/AO type B and C fractures. Acknowledging the restricted visibility of posterior segments, whose reduction and fixation is crucial for long-term success, our findings implicate the use of posterior approaches more often in the treatment of tibial plateau fractures. Also, low-energy trauma was identified as an important cause for tibial plateau fractures.

Significant pain reduction and improved functional outcome after surgery for displaced midshaft clavicular fractures.

PURPOSE: Displaced midshaft clavicular fractures can be treated conservatively as well as operatively by titan elastic nail (TEN) or plate fixation. This survey was performed to evaluate the clinical results of each treatment method and elaborate advantages or possible complications of each modality. METHODS: Between 2008 and 2013, 102 patients were prospectively included in our study-37 patients for conservative treatment with a rucksack bandage for 4 to 6 weeks, 41 patients for plate osteosynthesis, and 24 for intramedullary stabilization with TEN. Disabilities of the Arm, Shoulder and Hand (DASH), Constant Murley Score (CMS), and visual analog scale (VAS) for pain and function as well as time of invalidity were recorded over a 1-year period. RESULTS: The clinical data collected reveals that all three different therapies lead to good or excellent clinical results after 1 year. However, one can observe advantages of operative treatment in comparison to conservative therapy in some characteristics. CONCLUSION: Our data shows that there are several indications where operative treatment has advantages compared to conservative treatment. In special fracture types (Robinson 2B1), TEN gives the best results. Plate fixation is extraordinarily sufficient in pain reduction within the first 5 weeks and indicated in more-part fractures (Robinson 2B2). Nevertheless, conservative treatment is always a good and promising way to treat clavicular fractures, so that individual indications and thorough patient informative talks are inevitable.

Bunnell or cross-lock Bunnell suture for tendon repair? Defining the biomechanical role of suture pretension.

BACKGROUND: Suture pretension during tendon repair is supposed to increase the resistance to gap formation. However, its effects on the Bunnell suture technique are unknown. The purpose of this study was to determine the biomechanical effects of suture pretension on the Bunnell and cross-lock Bunnell techniques for tendon repair. METHODS: Eighty porcine hindlimb tendons were randomly assigned to four different tendon repair groups: those repaired with or without suture pretension using either a simple Bunnell or cross-lock Bunnell technique. Pretension was applied as a 10 % shortening of the sutured tendon. After measuring the cross-sectional diameter at the repair site, static and cyclic biomechanical tests were conducted to evaluate the initial and 5-mm gap formation forces, elongation during cyclic loading, maximum tensile strength, and mode of failure. The suture failure mechanism was also separately assessed fluoroscopically in two tendons that were repaired with steel wire. RESULTS: Suture pretension was accompanied by a 10 to 15 % increase in the tendon diameter at the repair site. Therefore, suture pretension with the Bunnell and cross-lock Bunnell repair techniques noticeably increased the resistance to initial gap formation and 5-mm gap formation. The tension-free cross-lock Bunnell repair demonstrated more resistance to initial and 5-mm gap formation, less elongation, and higher maximum tensile strength than the tension-free Bunnell repair technique. The only difference between the tensioned cross-lock Bunnell and tensioned Bunnell techniques was a larger resistance to 5-mm gap formation with the cross-lock Bunnell technique. Use of the simple instead of cross-lock suture configuration led to failure by suture cut out, as demonstrated fluoroscopically. CONCLUSION: Based on these results, suture pretension decreases gapping and elongation after tendon repair, and those effects are stronger when using a cross-lock, rather than a regular Bunnell suture. However, pretension causes an unfavorable increase in the tendon diameter at the repair site, which may adversely affect wound healing.

Mono- versus polyaxial locking plates in distal femur fractures: a prospective randomized multicentre clinical trial.

PURPOSE: Treatment of complex fractures of the distal femur utilizing monoaxial locking plates (e.g. Less Invasive Stabilisation System, LISS®, Synthes) is considered to be superior to conventional plating systems. Due to the limitation that the thread forces the screw into pre-determined positions, modifications have been made to allow screw positioning within a range of 30° (Non Contact Bridging, NCB®-DF, Zimmer). For the first time, this multicenter prospective randomized clinical trial (RCT) investigates the outcome of LISS® vs. NCB®-DF treatment following complex fractures of the distal femur. METHODS: Since June 2008, 27 patients with a fracture of the distal femur (AO ASIF 33-A-C and periprosthetic fractures) were enrolled in this study by four university trauma centres in southern Germany. Clinical (e.g. range of motion, Oxford knee score, Tegner score) and radiological (e.g. axis deviation, secondary loss of realignment) follow-ups were conducted one and six weeks, as well as three, six, and 12 months after the operation. RESULTS: This study comprises data of 27 patients (8 male, 19 female; 15 NCB®-DF, 12 LISS®). Polyaxial osteosynthesis using the NCB® system tended to result in better functional knee scores and a higher range of motion. Interestingly, fracture union tended to be more rapid using the polyaxial plating system. CONCLUSIONS: We present the analysis of a multicenter prospective RCT to compare the monoaxial LISS® vs. the polyaxial NCB®-DF treatment following complex fractures of the distal femur. NCB®-DF treatment tended to result in better functional and radiological outcomes than LISS® treatment. LEVEL OF EVIDENCE: Level I.

Medium-term results after complex intra-articular fractures of the tibial plateau.

BACKGROUND: To present the medium-term results of intra-articular, bicondylar AO/OTA classification type C fractures of the tibial plateau in a retrospective study at a level-1 trauma center in 22 patients with 23 fractures. METHODS: Demographic data for the patients and details of current clinical and radiological follow-up findings were obtained to assess range of motion, clinical stability and alignment of the knee, and posttraumatic arthrosis (Kellgren/Lawrence score). Functional outcomes were assessed using the Lysholm score, Knee Injury and Osteoarthritis Outcome Score (KOOS), and International Knee Documentation Committee (IKDC) form. RESULTS: Patients' mean age was 46 years (range 20-67 years). Leading causes of the fractures were high-energy traffic accidents and falls. There were seven C1, seven C2, and nine C3 fractures. ORIF was performed in 20 patients; in two patients an external fixator and in one patient cannulated screws alone were used. In 13/22 patients, an angle-stable locking plate (Less Invasive Stabilization System, LISS) was used for osteosynthesis. The mean follow-up period was 67 months (range 36-109 months). The overall complication rate was 39.1%, including four infections and four cases of pseudarthrosis (17.4%). The average flexion of the injured knee was significantly lower in comparison with the contralateral side (124.9° vs. 135.2°). Knee stability did not differ statistically significantly. Current radiographs revealed no signs of posttraumatic arthrosis in 30.4% of cases, mild signs in 34.8%, clear signs in 26.1%, and severe signs in 13% using the Kellgren and Lawrence scale. The average Lysholm score was 66.2 points, and the average KOOS score was 67.84. One patient was in category A, and 2 were in category B in the IKDC overall categories, whereas 5 patients were in category C and 14 were even in category D. CONCLUSIONS: Complex articular tibial plateau fractures are associated with a high rate of complications, continue to have a severe impact on function in the injured knee, lead to early post-traumatic arthrosis, and result in long-lasting subjective symptoms for the patients.

Biomechanical comparison of the Locking Compression superior anterior clavicle plate with seven and ten hole reconstruction plates in midshaft clavicle fracture stabilisation.

PURPOSE: The purpose of this study was to characterise the biomechanical properties of the seven hole superior anterior clavicle LCP (locking compression plate) and to compare these with the properties of commonly applied implants used for the stabilisation of clavicular midshaft fractures such as the locking 7- and ten hole reconstruction plate. METHODS: Twenty-four synthetic clavicles were used. A transverse midshaft fracture was induced. The clavicles were fixed with angle stable clavicle LCPs, seven hole and ten hole reconstruction plates (n = 8 each). Twenty cycles of axial compression and torsion were performed for each sample, which was followed by 1,000 cycles of three point bending and ultimately bending to failure. Axial, torsional and cantilever bending stiffness were calculated from the data recorded. RESULTS: The clavicle LCP showed the highest overall stiffness compared to the seven and ten hole reconstruction plate. Significantly higher stiffness values were found for axial compression and external rotation. In the load-to-failure tests, the ten hole reconstruction plate especially showed early signs of plastic deformation, which might account for early plate insufficiency so frequently observed clinically. CONCLUSION: The results indicate that the clavicle LCP, as compared to the reconstruction plates, leads to superior biomechanical stability in the treatment of midshaft clavicle fractures.