| Knee dislocation | |
|---|---|
 | |
| Plain lateral X-ray of the left knee showing a posterior knee dislocation[1] | |
| Symptoms | Knee pain, knee deformity[2] |
| Complications | Injury to the artery behind the knee, compartment syndrome[3][4] |
| Types | Anterior, posterior, lateral, medial, rotatory[4] |
| Causes | Trauma[3] |
| Diagnostic method | Based on history of the injury and physical examination, supported by medical imaging[5][2] |
| Differential diagnosis | Femur fracture, tibial fracture, patellar dislocation, ACL tear[6] |
| Treatment | Reduction, splinting, surgery[4] |
| Prognosis | 10% risk of amputation[4] |
| Frequency | 1 per 100,000 per year[3] |
A knee dislocation is a knee injury in which there is a complete disruption of the joint between the tibia and the femur.[3][4] Symptoms include knee pain and instability of the knee.[2] Complications may include injury to an artery around the knee, most commonly the artery behind the knee, or compartment syndrome.[3][4][7]
About half of cases are the result of major trauma and about half occur as a result of minor trauma.[3] In about half of cases the joint reduces itself before a person arrives at the hospital.[3] Typically there is a break of the anterior cruciate ligament, posterior cruciate ligament, and either the medial collateral ligament or lateral collateral ligament.[3] If the ankle–brachial pressure index is less than 0.9, CT angiography is recommended to detect blood vessel injury.[3] Otherwise repeated physical exams may be sufficient.[2]
If the joint remains dislocated, reduction and splinting is indicated;[4] this is typically carried out under procedural sedation.[2] In those with signs of arterial injury, immediate surgery is generally carried out.[3] Multiple surgeries may be required.[4] In just over 10% of cases, an amputation of part of the leg is required.[4]
Knee dislocations are rare, occurring in about 1 per 100,000 people per year.[3] Males are more often affected than females.[2] Younger adults are most often affected.[2] Descriptions of this injury date back to at least 20 BC by Meges of Sidon.[8]
References edit
- ^ Duprey, K; Lin, M (February 2010). "Posterior knee dislocation". The Western Journal of Emergency Medicine. 11 (1): 103–4. PMC 2850837. PMID 20411095.
- ^ a b c d e f g Boyce, RH; Singh, K; Obremskey, WT (December 2015). "Acute Management of Traumatic Knee Dislocations for the Generalist". The Journal of the American Academy of Orthopaedic Surgeons. 23 (12): 761–8. doi:10.5435/JAAOS-D-14-00349. PMID 26493970.
- ^ a b c d e f g h i j k Maslaris, A; Brinkmann, O; Bungartz, M; Krettek, C; Jagodzinski, M; Liodakis, E (22 February 2018). "Management of knee dislocation prior to ligament reconstruction: What is the current evidence? Update of a universal treatment algorithm". European Journal of Orthopaedic Surgery & Traumatology : Orthopedie Traumatologie. 28 (6): 1001–1015. doi:10.1007/s00590-018-2148-4. PMID 29470650.(subscription required)
- ^ a b c d e f g h i Bryant, Brandon; Musahl, Volkar; Harner, Christopher D. (2011). "59. The Dislocated Knee". In W. Norman Scott (ed.). Insall & Scott Surgery of the Knee E-Book (5th ed.). Elsevier Churchill Livingstone. p. 565. ISBN 978-1-4377-1503-3.
- ^ Cite error: The named reference
Lac2015was invoked but never defined (see the help page). - ^ Eiff, M. Patrice; Hatch, Robert L. (2011). Fracture Management for Primary Care E-Book. Elsevier Health Sciences. p. ix. ISBN 978-1455725021.
- ^ Medina, O; Arom, GA; Yeranosian, MG; Petrigliano, FA; McAllister, DR (September 2014). "Vascular and nerve injury after knee dislocation: a systematic review". Clinical Orthopaedics and Related Research. 472 (9): 2621–9. doi:10.1007/s11999-014-3511-3. PMC 4117866. PMID 24554457.
- ^ Elliott, James Sands (1914). Outlines of Greek and Roman Medicine. Creatikron Company. p. 76. ISBN 9781449985219.