Inflammatory tissue response in human soft tissue is caused by a higher particle load near carbon fiber-reinforced PEEK compared to titanium plates.

Titanium as the leading implant material in locked plating is challenged by polymers such as carbon fiber-reinforced polyetheretherketone (CFR-PEEK), which became the focus of interest of researchers and manufacturers in recent years. However, data on human tissue response to these new implant materials are rare. Osteosynthesis plates and peri­implant soft tissue samples of 16 healed proximal humerus fractures were examined (n = 8 CFR-PEEK, n = 8 titanium). Soft tissue was analyzed by immunohistochemistry and µCT. The entrapped foreign bodies were further examined for their material composition by FTIR. To gain insight into their origin and formation mechanism, explanted and new plates were evaluated by SEM, EDX, profilometry and HR-CT. In the peri­implant soft tissue of the CFR-PEEK plates, an inflammatory tissue reaction was detected. Tissues contained foreign bodies, which could be identified as tantalum wires, carbon fiber fragments and PEEK particles. Titanium particles were also found in the peri­implant soft tissue of the titanium plates but showed a less intense surrounding tissue inflammation in immunohistochemistry. The surface of explanted CFR-PEEK plates was rougher and showed exposed and broken carbon fibers as well as protruding and deformed tantalum wires, especially in used screw holes, whereas scratches were identified on the titanium plate surfaces. Particles were present in the peri­implant soft tissue neighboring both implant materials and could be clearly assigned to the plate material. Particles from both plate materials caused detectable tissue inflammation, with more inflammatory cells found in soft tissue over CFR-PEEK plates than over titanium plates. STATEMENT OF SIGNIFICANCE: Osteosynthesis plates are ubiquitously used in various medical specialties for the reconstruction of bone fractures and defects and are therefore indispensable for trauma surgeons, ENT specialists and many others. The leading implant material are metals such as titanium, but recently implants made of polymers such as carbon fiber-reinforced polyetheretherketone (CFR-PEEK) have become increasingly popular. However, little is known about human tissue reaction and particle generation related to these new implant types. To clarify this question, 16 osteosynthesis plates (n = 8 titanium and n = 8 CFR-PEEK) and the overlying soft tissue were analyzed regarding particle occurrence and tissue inflammation. Tissue inflammation is clinically relevant for the development of scar tissue, which is discussed to cause movement restrictions and thus contributes significantly to patient outcome.

Open reduction and internal fixation of displaced head-split type humeral fractures and role of the rotator-interval approach.

Background: Open reduction and internal fixation (ORIF) of humeral head split fractures is challenging because of high instability and limited visibility. The aim of this retrospective study was to investigate the extend of the approach through the rotator interval (RI) on the reduction quality and functional outcome. Methods: 37 patients (mean age: 59 ± 16 years,16 female) treated by ORIF through a standard deltopectoral (DP) approach were evaluated. The follow-up period was at least two years. In 17 cases, the approach was extended through the RI. Evaluation was based on radiographs, Constant scores (CS) and DASH scores. Results: In group DP, "anatomic" reduction was achieved in 9 cases (45%), "acceptable" in 5 cases (25%), and "malreduced" in 6 cases (30%). In group RI, "anatomic" reduction was seen in 12 cases (71%), "acceptable" in 5 cases (29%), and "malreduced" in none (p = 0.04). In the DP group, the CS was 60.2 ± 16.2 and the %CS was 63.9 ± 22.3, while in the RI group, the CS was 74.5 ± 17.4 and the %CS was 79.1 ± 24.1 (p = 0.07, p = 0.08). DASH score was 22.8 ± 19.5 in DP compared to RI: 25.2 ± 20.6 (p = 0.53). Conclusions: The RI approach improves visualization as it enhances quality of fracture reduction, however functional outcomes may not differ significantly. Type of study and level of proof: Retrospective, level III.

Functional outcomes before and after implant removal in patients with posttraumatic shoulder stiffness and healed proximal humerus fractures: does implant material (PEEK vs. titanium) have an impact? - a pilot study.

BACKGROUND: Posttraumatic shoulder stiffness remains a problem after proximal humerus fracture (PHF) despite good healing rates. The aim of this pilot study was to determine whether the implant material and overlying soft tissue have an effect on shoulder range of motion (ROM) before and after implant removal (IR). METHODS: 16 patients (mean age 55.2 ± 15.3 (SD) years; 62.5% female) were included who underwent operative treatment with locking plates of either carbon fiber reinforced Polyetheretherketone (PEEK) (PEEKPower® humeral fracture plate, Arthrex, Naples, Florida, USA, n = 8) or titanium alloy (Ti) (Philos®, DePuy Synthes, Johnson & Johnson Medical, Raynham, Massachusetts, USA, n = 8) for PHF. All patients presented with a limited ROM and persistent pain in everyday life after the fracture had healed, whereupon IR was indicated. ROM before and after IR were compared as well as the Constant Score (CS) and the CS compared to the contralateral shoulder (%CS) 1 year after IR. RESULTS: In group PEEK, elevation was 116.3° ± 19.2° pre- and 129.4° ± 23.7° post-IR (p = 0.027). External rotation was 35.0° ± 7.6° pre- and 50.6° ± 21.8° post-IR (p = 0.041). External rotation with the humerus abducted 90° was 38.8° ± 18.1° pre- and 52.5° ± 25.5° post-IR (p = 0.024). In group Ti, elevation was 110.0° ± 34.6° pre- and 133.8° ± 31.1° post-IR (p = 0.011). External rotation with the humerus at rest was 33.8° ± 23.1° pre- and 48.8° ± 18.7° post-IR (p = 0.048). External rotation with the humerus abducted 90° was 40.0° ± 31.6° pre- and 52.5° ± 22.5° post-IR (p = 0.011). Comparison of the two implant materials showed no significant difference. The overall CS was 90.3 ± 8.8, the %CS was 91.8% ± 14.7%. CONCLUSION: There was no significant difference in ROM, CS and %CS with respect to plate materials, although lower cell adhesion is reported for the hydrophobic PEEK. However, all patients showed improved functional outcomes after IR in this pilot study. In patients with shoulder stiffness following locked plating for PHF, implants should be removed and open arthrolysis should be performed, independently from the hardware material. LEVEL OF EVIDENCE: II.

[Rotator cuff tear : Indications and pathology-specific reconstructive procedures]. / Rotatorenmanschettenruptur : Indikationen und pathologiespezifische rekonstruktive Verfahren.

Rotator cuff (RC) tears comprise a broad spectrum of lesions ranging from partial to full thickness tears of a single tendon and massive cuff tears. Both glenohumeral trauma as well as degenerative processes can result in tearing of the RC. Treatment therefore requires a meticulous diagnosis as well as a differentiated approach by careful consideration of morphological and patient-specific factors. The pathogenesis, tear morphology, clinical symptoms and functional demands of the patient determine the therapeutic approach. Despite pathological and individual patient-related factors, early surgical repair is generally recommended for traumatic RC tears in young patients and in patients with high functional demands due to the high risk of tear progression. The results of RC repair are negatively correlated with the size of the lesion, the number of tendons involved, the degree of tendon retraction, muscular alteration and patient age. This article provides an overview of the various pathogenesis, indications and surgical repair of RC tears with respect to modern pathology-specific reconstructive procedures.

Varus malposition relates to functional outcomes following open reduction and internal fixation for proximal humeral fractures: A retrospective comparative cohort study with minimum 2 years follow-up.

BACKGROUND: The aim of this study was to evaluate functional outcomes in patients with varus malposition following open reduction and internal fixation of displaced proximal humeral fractures. METHODS: Data of 685 patients with a mean age of 67±15.8 years (67% female), that were treated by open reduction and internal fixation for a displaced proximal humeral fracture at a level 1 trauma center, were analyzed. On standardized x-ray imaging, the degree of varus displacement was measured over a minimum of two years follow-up and patients were divided into three groups. Group A: anatomic or <10° of varus or valgus malposition, group B: 10-20° of varus malposition and group C: >20° varus malposition, while anatomic head-shaft-angle was defined 135° The groups were compared with regards to functional outcomes by means of the Constant Score (CS). RESULTS: In 565 patients with anatomic to minor <10° varus or valgus malposition (Group A), the mean CS was 72.5 ± 18.8 points. The %CS to the uninjured side was 87.2 ± 24.1 and the age and gender normalized nCS was 84.7 ± 21.7. In comparison, in group B (10-20° varus) the mean CS was 64.7 ± 16.9, the mean %CS was 84.5 ± 18.3 and the mean nCS was 76.2 ± 20.6. In group C (>20° varus) the mean CS was 54.1 ± 19.5, the mean was %CS: 72.3 ± 26.4 and the mean nCS was 64.8 ± 23.8 (p = 0.02, p = 0.03, p = 0.01). Overall, the CS, %CS and nCS correlated significantly with the degree of varus position (Pearson correlation, r = 0.23, r = 0.21, r = 0.25). CONCLUSION: Varus malposition is related to inferior functional outcomes compared to anatomic healing in patients treated by open reduction and internal fixation for proximal humeral fractures. The data supports suggestions to prevent varus malposition in open reduction and internal fixation. In severe >20° of varus malposition, revision surgery should be considered.

Eradication of Acinetobacter baumannii/Enterobacter cloacae complex in an open proximal tibial fracture and closed drop foot correction with a multidisciplinary approach using the Taylor Spatial Frame®: a case report.

BACKGROUND: Multi-drug-resistant bacteria (e.g. Carbapenem-resistant Acinetobacter baumannii, extended-spectrum betalactamase or carbapenemase-producing enterobacteriaceae) are emerging in early-onset infections. So far, there is no report describing the eradication of these bacteria in a osseous infection of an open proximal tibial fracture in combination with the hexapod technology to address both osseous consolidation and closed drop foot correction. CASE PRESENTATION: After sustaining a proximal tibial fracture (Gustilo 3B), a 41-year-old man was primarily treated with open reduction and internal fixation by a locking plate and split-thickness skin graft in the home country. At the time of admission to our hospital there was a significant anterolateral soft tissue defect covered with an already-necrotic split-thickness graft and suspicious secretion. CAT and MRI scans revealed no signs of osseous healing, intramedullary distinctive osteomyelitis, as well as a large abscess zone in the dorsal compartment. Multiple wound smears showed multi-drug-resistant bacteria: Acinetobacter baumannii (Carbapenem resistant) as well as Enterobacter cloacae complex (AmpC overexpression). After implant removal, excessive osseous and intramedullary debridements using the Reamer Irrigator Aspirator (RIA®) as well as initial negative pressure wound therapy were performed. Colistin hand-modelled chains and sticks were applied topically as well as an adjusted systemic antibiotic scheme was applied. After repetitive surgical interventions, the smears showed bacterial eradication and the patient underwent soft tissue reconstruction with a free vascularized latissimus dorsi muscle flap. External fixation was converted to a hexapod fixator (TSF®) to correct primary varus displacement, axial assignment and secure osseous healing. A second ring was mounted to address the fixed drop foot in a closed fashion without further intervention. At final follow-up, 12 months after trauma, the patient showed good functional recovery with osseous healing, intact soft tissue with satisfactory cosmetics and no signs of reinfection. CONCLUSIONS: A multidisciplinary approach with orthopaedic surgeons for debridement, planning and establishing osseous and joint correction and consolidation, plastic surgeons for microvascular muscle flaps for soft tissue defect coverage as well as clinical microbiologists for the optimized anti-infective treatment is essential in these challenging rare cases. LEVEL OF EVIDENCE: Level IV.

[Tendonitis calcarea of the piriformis muscle in a young amateur athlete]. / Tendinitis calcarea des M. piriformis bei einer jungen Amateursportlerin.

Distinct calcific tendonitis associated with chronic pain refractory to conservative treatment can require operative treatment. Symptomatic calcific tendonitis of the piriform muscle, despite calcific tendonitis of other regions, is an extremely rare diagnosis. We report about a young athlete with persistent gluteal pain despite long-term conservative treatment. MRI scans revealed tendonitis calcarea with surrounding soft tissue inflammation. On open surgical removal of the calcification, pain symptoms were relieved and the patient was able to return to sports.

[Therapy of acute acromioclavicular joint instability. Meta-analysis of arthroscopic/minimally invasive versus open procedures]. / Therapie der akuten AC-Gelenk-Instabilität. Eine Metaanalyse arthroskopischer/minimal-invasiver vs. offener Verfahren.

BACKGROUND: A variety of surgical procedure are desrcibed for the treatment of acute acromioclavicular (AC-) joint injuries. Beside open techniques arthroscopic assisted procedures spread widely. Each surgical technique offers advantages and disadvantages, but none is currently accepted as a gold standard. Therefore, the study aims to review the evidence for arthroscopic and open surgical procedures in the treatment of acute AC joint instabilities. MATERIAL AND METHODS: According to the Cochrane Handbook for Systematic Reviews of Interventions we conducted a defined search of Medline and Embase database for articles publisher over the last ten years. RESULTS: The search resulted in 961 studies of which 32 were included in this review and 3 studies were suitable for a meta-analysis. The functional outcome (Constant score) showed a tendency towards better results after arthroscopic procedures (weighted mean difference 5.60, 95% confidence interval 0.36-10.64). There were no significant differences with respect to complication rates, secondary dislocation in the vertical plane, revision surgery and AC joint instability. CONCLUSION: There is insufficient evidence to inform the surgical management of acute AC joint instability. Due to inconsistent study designs there is no evidence for a general superiority of any of the open or arthroscopic procedures. Randomized, controlled studies are necessary to demonstrate whether arthroscopic techniques show a potential benefit in terms of a better functional outcome.

[Combined ac joint dislocation and distal clavicle fracture. Closed reduction and arthroscopically assisted coracoclavicular fixation]. / Kombinierte AC-Gelenk-Luxation und laterale Klavikulafraktur. Geschlossene Reposition und arthroskopisch gestützte korakoklavikuläre Fixierung.

BACKGROUND: A 55-year-old male patient sustained a dislocation of the acromioclavicular (AC) joint in combination with a distal clavicle fracture. METHODS: Following closed reduction of the fractured clavicle, arthroscopically assisted coracoclavicular fixation was performed. DISCUSSION AND CONCLUSION: A combined injury of a complete ac joint dislocation and a distal clavicle fracture is rare and is not included in currently available classification systems; therefore, in this article a classification and assessment of the stability of this injury as well as appropriate treatment options are discussed.