[Operative treatment of osseous pull out of the extensor tendon using a hook plate]. / Die Versorgung der dorsalen Endphalanxbasisfraktur der Langfinger mittels Hakenplatte.

OBJECTIVE: Anatomical reposition and stabilization of dorsal distal phalanx fractures with a hook plate. INDICATIONS: Dislocated mallet fractures type Doyle IVb with dislocation of the fragment by more than 2 mm and/or tilting of the fragment as well as dislocation of the dorsal distal phalanx fractures type Doyle IVc. CONTRAINDICATIONS: Florid inflammation of and injuries to the soft tissues in the operation area. SURGICAL TECHNIQUE: Dorsal approach to the distal interphalangeal joint (Y-, S-, H-shaped). Preparation of the fragment, cleaning the fracture gap, repositioning of the fragment, mounting of the plate, placing the screw. Controlling by image converter. Suture of the skin; tape. POSTOPERATIVE MANAGEMENT: Stack splint for 4 weeks. After week 3, start with exercising of the distal interphalangeal joint within the splint. Physiotherapy is usually not required. Full exertion after 6-8 weeks is possible. The period of inability to work is dependent on the patient's occupation. Due to the danger of perforation and infection, it is recommended that the plate be removed after 3-6 months. RESULTS: From February 2002 to September 2009, 77 mallet fractures type Doyle IVb and IVc were operatively stabilized with a hook plate. In a retrospective study, 59 patients were followed up at a mean interval of 38.3 (3-69) months after the operation. Wound healing problems or inflammation were not observed. Visible disturbances of nail growth were macroscopically seen in 11.9%. Results were very good in 35 patients (59.3%), good in 16 patients (27.1%), sufficient in 5 patients (8.5%), satisfying in 1 patient (1.7%), and insufficient in 2 patients (3.4%).

[Elution kinetics and antimicrobial effects of gentamicin- and clindamycin-loaded bone cements in vitro]. / In-vitro-Untersuchungen zu Elutionskinetiken und antimikrobiellen Wirkungen von Gentamicin- und Clindamycin-haltigen Knochenzementen.

AIMS: In arthroplasty and particulary in revision surgery antibiotic-loaded bone cements are applied. The purpose of the current study was to analyse the kinetics of antibiotic release and antimicrobial effects of the gentamicin- and clindamycin-loaded bone cement Versabond. MATERIALS AND METHODS: Test cylinders of bone cements, containing gentamicin and clindamycin in different concentrations, were investigated in vitro with regards to the kinetics of antibiotic release by applying static and continuous elution methods. Antimicrobial effects of antibiotic-loaded bone cement were tested in an infection model with different strains of Staphylococcus aureus and Staphylococcus epidermidis and live/dead dye plus fluorescence microscopy. For the surface analysis of antibiotic-loaded test cylinders contaminated with Staphylococcus epidermidis, scanning electron microscopy was used. RESULTS: The measurement of static and continuous elution revealed initially higher rates of gentamicin release in comparison with clindamycin. The gentamicin amount decreased within 24 h, whereas clindamycin-loaded test cylinders showed a prolonged release. After 24 h exclusive avital bacteria on antibiotic-loaded cement cylinders were seen, after 72 h on gentamicin-loaded cement bacterial growth was again detected. Application of antibiotics in bone cement revealed an inhomogeneous surface of the bone cement cylinder. CONCLUSIONS: On application of clindamycin in bone cement the features of increased antibiotic uptake and antimicrobial effect compared with gentamicin-loaded bone cement are observed.