title: Current concepts review: Fractures of the patella.
abstract: Fractures of the patella account for about 1% of all skeletal injuries and can lead to profound impairment due to its crucial function in the extensor mechanism of the knee. Diagnosis is based on the injury mechanism, physical examination and radiological findings. While the clinical diagnosis is often distinct, there are numerous treatment options available. The type of treatment as well as the optimum timing of surgical intervention depends on the underlying fracture type, the associated soft tissue damage, patient factors (i.e. age, bone quality, activity level and compliance) and the stability of the extensor mechanism. Regardless of the treatment method an early rehabilitation is recommended in order to avoid contractures of the knee joint capsule and cartilage degeneration. For non-displaced and dislocated non-comminuted transverse patellar fractures (2-part) modified anterior tension band wiring is the treatment of choice and can be combined - due to its biomechanical superiority - with cannulated screw fixation. In severe comminuted fractures, open reduction and fixation with small fragment screws or new angular stable plates for anatomic restoration of the retropatellar surface and extension mechanism results in best outcome. Additional circular cerclage wiring using either typical metal cerclage wires or resorbable PDS/non-resorbable FiberWires increases fixation stability and decreases risk for re-dislocation. Distal avulsion fractures should be fixed with small fragment screws and should be protected by a transtibial McLaughlin cerclage. Partial or complete patellectomy should be regarded only as a very rare salvage operation due to its severe functional impairment.
authors.affiliation: Center for Musculoskeletal Surgery, Charité - University Medicine Berlin, Germany.
authors.forename: Clemens
authors.initials: C
authors.lastname: Gwinner
authors.affiliation: Center for Musculoskeletal Surgery, Charité - University Medicine Berlin, Germany.
authors.forename: Sven
authors.initials: S
authors.lastname: Märdian
authors.affiliation: Center for Musculoskeletal Surgery, Charité - University Medicine Berlin, Germany.
authors.forename: Philipp
authors.initials: P
authors.lastname: Schwabe
authors.affiliation: Department of Orthopaedics and Trauma Surgery - University Hospital Dresden, Germany.
authors.forename: Klaus-D
authors.initials: KD
authors.lastname: Schaser
authors.affiliation: Center for Musculoskeletal Surgery, Charité - University Medicine Berlin, Germany; Department of Plastic and Hand Surgery, St. Marien-Krankenhaus Berlin, Germany.
authors.forename: Björn Dirk
authors.initials: BD
authors.lastname: Krapohl
authors.affiliation: Center for Musculoskeletal Surgery, Charité - University Medicine Berlin, Germany.
authors.forename: Tobias M
authors.initials: TM
authors.lastname: Jung
keywords: biomechanics; conservative treatment; patellar fracture; patellectomy; tension band
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