Book contents
- Frontmatter
- Dedication
- Contents
- List of contributors
- Preface
- Acknowledgments
- Part I Upper extremity
- Part II Pelvis and acetabulum
- Part III Lower extremity
- Chapter 9
- Chapter 10
- Chapter 11
- Fractures of the patella
- Chapter 12
- Chapter 13
- Chapter 14
- Part IV Spine
- Part V Tendon injuries
- Part VI Compartments
- References
- Index
Fractures of the patella
from Chapter 11
Published online by Cambridge University Press: 05 February 2015
- Frontmatter
- Dedication
- Contents
- List of contributors
- Preface
- Acknowledgments
- Part I Upper extremity
- Part II Pelvis and acetabulum
- Part III Lower extremity
- Chapter 9
- Chapter 10
- Chapter 11
- Fractures of the patella
- Chapter 12
- Chapter 13
- Chapter 14
- Part IV Spine
- Part V Tendon injuries
- Part VI Compartments
- References
- Index
Summary
TENSION BAND WIRING
Implants for patellar fractures have to resist high-tensile stress. Tension band wiring transforms distraction forces of the extensor mechanism to compression forces. The wires provide anchorage for the tension band wire and neutralize the rotational forces.
Indications
Transverse and multifragmental patellar fractures. In case of multifragmental fractures, often a combination of tension band wiring and cortical screws, lag screws, K-wires or cerclage wires is necessary.
A pair of lag screws can exert high-compression forces to transverse fractures.
Pre-operative planning
Clinical assessment
Pain, swelling, deformity, haemarthrosis, loss of function.
Palpate gap between the fragments. Rule out an injury of the quadriceps and patellar tendon.
Soft tissue injuries like abrasions arecommonandmay require debridement or delayed operation, in order to reduce the risk of infection.
Assess neurovascular status of the leg.
Radiological assessment
Analyse fracture geometryby standardanteroposterior (AP) and lateral X-rays, and a tangential patellar view (Fig. 11.1).
Differentiate between fractures and growth abnormalities (e.g. a bipartite patella is typically found on the proximal lateral quadrant of the patella, usually with sclerotic edges of the fragment in contrast to fractures).
Rule out an abnormal patellar position caused by isolatedquadriceps or patellartendonruptures.TheInsall index calculates the ratio of greatest patellar lengthand the distance between the distal patellar pole and the tibial tuberosity. Normal ratio = 1; a ratio < 1 suggests a patellar tendon rupture. If in doubt, compare with the lateral view of the contralateral side. Ultrasound reveals the tendon rupture site and haematoma.
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- Practical Procedures in Orthopaedic Trauma Surgery , pp. 206 - 209Publisher: Cambridge University PressPrint publication year: 2006