[Plate osteosynthesis after patellar fracture - the technique and initial results of a prospective study]. / Die Plattenosteosynthese der Patellafraktur ­ Technik und erste Ergebnisse einer prospektiven Studie.

BACKGROUND: Tension band wiring after patellar fractures is related to a high number of implant-related complications (22-53 %). Revision surgery is necessary in 10-55 % of patients mostly with unsatisfactory results. The patella plate is an alternative treatment with the advantages of locked plating. The purpose of this study was to evaluate the first clinical prospective results and complications of this new implant. MATERIALS AND METHODS: Between April 2013 and May 2015 all patients that were treated with locked plating for patella fractures were included in this prospective study. Patients were followed-up clinically after six weeks and six months. RESULTS: Included in this study were 17 patients, 6 women and 11 men, with a mean age of 58 years (19-87). The knee range of motion was 120° after 6 weeks and improved to 138° after 6 months, corresponding to 84 % and 97 % of the range of motion of the healthy opposite knee. The Tegner activity scale increased from 2,5 to 3,5 (initial value: 4), the Lysholm score increased from 78 to 92 points (initial value: 97) and the Kujala score increased from 72 to 88 points (initial value: 96). Two complications occurred: one patient had a reactive bursitis prepatellaris and one patient sustained a loss of reduction. CONCLUSION: Locked plating of patella fractures is a reliable alternative treatment with good functional outcomes and low complication rates.

[Injuries of the acromioclavicular joint: Hook plate versus arthroscopy]. / Verletzungen des Akromioklavikulargelenks : Hakenplatte vs. Arthroskopie.

Acute acromioclavicular (AC) joint injuries are common in clinical practice. The hook plate is a well-established conventional operative treatment option for high grade instability; however, arthroscopically-assisted flexible double button techniques are increasingly being used. Both procedures lead to good or excellent results. The advantages of the hook plate are the simple surgical technique and the possibility of an early functional aftercare. The minimally invasive one-step procedure with the possibility of identification and treatment of frequently concomitant glenohumeral pathologies is advantageous for the arthroscopic technique but mobilization is more restrictive. Available comparative studies have shown no significant clinical differences but a tendency towards better results with a higher degree of acceptance among patients for the arthroscopic and minimally invasive non-rigid double button procedures.

[Current trends in reverse fracture arthroplasty]. / Inverse Frakturprothese ­ eine Trendwende.

The reliable results of reverse arthroplasty have made this the preferred treatment method for non-reconstructable proximal humeral fractures. The individual consideration of the patient and the morphological features of the fractures are essential. Computed tomography (CT) images provide crucial information on the perfusion of the humeral head relevant for the prognosis and treatment. In this context a differentiation must be made between hard and soft criteria against a reconstruction. Tuberosities should be reduced whenever possible, because reverse arthroplasty with healed tuberosities provides a better range of motion and more strength for external rotation and anteversion, less complications and longer survival rates. In recent years the trend has been towards anatomical designs of prostheses with a humeral inclination of 135°. Revision rates for primary fracture prostheses are overall low with instability as the main reason for revision surgery, followed by periprosthetic fractures and infections. Reverse fracture arthroplasty has comparable or better clinical results compared to conservative treatment, osteosynthesis for geriatric patients, hemiarthroplasty and prosthesis implantation by elective surgery. Reverse arthroplasties, which were implanted in conditions of fracture sequelae, did not achieve significantly poorer clinical outcome at mid-term follow-up and can significantly improve shoulder function.

The stabilization effect of the conjoint tendon in reverse total shoulder arthroplasty.

BACKGROUND: Numerous factors determine stability of reverse total shoulder arthroplasty. The effect of the conjoint tendon in relation to stability remains unknown. In this biomechanical study, we evaluated the influence of the conjoint tendon on the anterior stability of reverse total shoulder arthroplasty with a hemispherical glenosphere and a glenosphere with 9 mm lateralisation. METHODS: A reverse total shoulder arthroplasty was implanted in 6 human cadaveric shoulders. The anterior stability was evaluated using a shoulder simulator. Two conditions, intact and dissected conjoint tendon, and 2 component configurations, a hemispherical glenosphere and a glenosphere with 9 mm lateralisation, were tested in each specimen. Testing of anterior stability was performed in 30° and 60° of abduction, with 0° and 30° of external rotation in the glenohumeral joint. FINDINGS: The conjoint tendon showed a significant influence on the anterior stability with a hemispherical glenosphere in 30° and 60° with neutral rotation (p = 0.028) as well as 30° abduction with 30° (p = 0.028) external rotation. The 9 mm lateralised glenosphere stabilized significantly reverse total shoulder arthroplasty with resected conjoint tendon compared to the hemispherical glenosphere with resected conjoint tendon (p = 0.028). INTERPRETATION: In a biomechanical setting the conjoint tendon has a stabilizing influence on the anterior stability of the reverse total shoulder arthroplasty with a hemispherical glenosphere in an abducted arm position, but this stabilizing effect was not seen with the lateralised glenosphere. The single influence of the lateralisation of the glenosphere on anterior stability was shown in cases of resected conjoint tendon.

Cement augmentation of humeral head screws reduces early implant-related complications after locked plating of proximal humeral fractures.

BACKGROUND: Cement augmentation (CA) of humeral head screws in locked plating of proximal humeral fractures (PHF) was found to be biomechanically beneficial. However, clinical outcomes of this treatment have not been well evaluated to date. OBJECTIVES: To assess outcomes of locked plating of PHF with additional CA and to compare them with outcomes of conventional locked plating without CA. METHODS: 24 patients (mean age, 74.2 ± 10.1 years; 22 female) with displaced PHF were prospectively enrolled and treated with locked plating and additional CA. The Constant score (CS), the Simple Shoulder Test (SST), and the Simple Shoulder Value (SSV) were assessed 3 and 12 months postoperatively. Fracture healing and potential complications were evaluated on postoperative radiographs. The CS and complications were compared with the outcomes of a matched group of 24 patients (mean age, 73.9 ± 9.4 years; 22 female) with locked plating of displaced PHF without CA. RESULTS: At the 3­month follow-up, the mean CS was 59.9 ± 15.6 points, the mean SST was 7.5 ± 2.7 points, and the mean SSV was 63.9 ± 21.7%. All scores significantly improved by the 12-month follow-up (p < 0.05; CS, 72.9 ± 17.7; SST, 9.2 ± 3.2; SSV, 77.2 ± 17.3%). There were two cases (8%) of biological complications (n = 1 varus malunion and n = 1 humeral head necrosis). Compared with locked plating without CA, no significant differences were observed between the CS at the 3­ (57.8 ± 13.4 points; p = 0.62) and 12-month (73.0 ± 12.8 points; p = 0.99) follow-up. However, patients without CA had a significantly increased risk of early loss of reduction and articular screw perforation (p = 0.037). CONCLUSION: Locked plating of proximal humeral fractures with trauma cement augmentation of humeral head screws could be translated from the ex-vivo lab setting into the clinical situation without additional complications. Locked plating of displaced PHF with additional cement augmentation showed similar clinical outcomes but reduced the rate of early implant-related complications compared to locked plating without additional CA.

[Osteoporotic fractures of the proximal humerus]. / Osteoporotische Frakturen am proximalen Humerus.

Fractures of the proximal humerus are typical osteoporotic fractures of the elderly with an increasing incidence. Computed tomography (CT) with 3D reconstruction plays a more and more decisive role in the diagnostics because of an improved understanding of fractures in 3D images. The resulting correct fracture classification has significance for the decision of the best therapy procedure. Currently an extended version of the Codman classification with its four and more fragments is used to give additive information about varus or valgus dislocation, impression or distraction. The comparison of conservative and operative treatment showed no predominance of one of the procedures, therefore both strategies are justified. An operative treatment is recommended in complex fractures. Thus, early functional mobilization, early self-dependence and return to the activities of daily living are possible. Intramedullary nailing is advised in 2-part fractures, in dislocated multipart fractures locking plating or a primary reverse shoulder arthroplasty with refixation of the tuberosities in patients over 75 years. However, the improved plate and nail systems with polyaxiality, calcar screws, modern plate and nails designs as well as the possibility of arthroscopy-assisted nail implantation or plate removal combined with arthroscopic arthrolysis are innovative.