Dr Luke Phillips Emergency Physician
Peer review: Dr EANNA Mac Suibhne
Welcome to Fast Fridays – a case-based, rapid review of a topic. The cases have been adapted from real patients but have been changed for anonymity and to emphasise key learning points.
23-year-old presents with knee pain and swelling post landing awkwardly on their right knee playing football. They now have pain and swelling to the knee and have difficulty weight bearing. On exam they have a large joint effusion and tenderness to lateral joint line. They can straight leg raise but any other assessment of knee joint integrity is limited by the swelling and pain.
Which patients actually need a knee X-ray?
Our Canadian friends, led by Stiell et al, have developed the Ottawa Knee Rule to identify low risk patients who may not need a knee X-ray.
A knee x-ray series is only needed for knee injury patients with any of these findings:
- Age ≥ 55, OR
- Isolated tenderness of patella (no bone tenderness of knee other than patella), OR
- Tenderness of head of fibula, OR
- Inability to flex to 90°, OR
- Inability to bear weight both immediately after injury and in the ED for 4 steps (unable to transfer weight twice onto each lower limb regardless of limping.
In an external validation study of the rule, the authors found a relative reduction in Knee x-rays of 26.4% and a sensitivity of 100% for detecting knee fractures and a specificity of 48%.
The patient met criteria for imaging and X-Rays were performed
What are the key findings on these x-rays?
- There is a moderate to large knee joint effusion.
- Avulsion fracture of the tibial spine at the distal ACL attachment.
- Avulsion fracture from the lateral knee capsule (Segond fracture).
What is the significance of this fracture pattern?
Segond fractures are avulsion fractures of the proximal-lateral tibia and represent a bony avulsion of the anterolateral ligament. It is associated with severe rotational instability of the knee. Identification of this finding on plain film radiographs should prompt further evaluation as they are rarely isolated injuries. They are pathognomonic for an Anterior Cruciate Ligament (ACL) tear, present in 75-100% of cases. Conversely, 9-12% of ACL ruptures have an associated Segond fracture. The presence of a tibial spine fracture and large haemarthrosis also indicates a likely ACL injury.
Eponymous Old White Man Alert
Paul Ferdinand Segond (1851–1912) was professor of surgery at the University of Paris and surgeon in chief at the Saltpetriere. Although Segond was one of the foremost “knee specialists” in 19th century France, his significant contributions in this area were overlooked, and he is chiefly remembered for his contributions to gynaecologic surgery.
What are the key management options?
Management initially should be supportive, encouraging ice application, elevation compression and simple analgesia. Patients should be having restricted weight baring (initially using crutches but can toe touch, then progress to foot down if standing) and if there is complete knee instability or loss of extensor mechanism (ie patella fracture or quad/ patella tendon rupture) they should be provided with a Zimmer splint in the short term. They should be encouraged to retain some movement while sitting/ lying. Gentle movement against gravity will help preserve quad strength, reduce effusion, retain range of movement & proprioception. Early Physio for “prehab” (“pre-op rehabilitation”) is really important. This makes the operation easier and can improve recovery in the longer term. Often patients will have operative management delayed until good ROM & strength similar (>90% of unaffected side).
Patients should have an early orthopaedic referral for consideration of operative management including open repair of the fracture along with the ACL. There is no evidence for fixing the Segond fracture itself, any surgical intervention undertaken is aimed at repairing associated injuries. MRI will likely assist in further differentiating the injury and decision-making about ongoing management.
Prognosis-wise, although Segond fractures are associated with a highly unstable knee, post-operative studies suggest no difference in tested stability after the ligamentous injury is addressed. Good news for our 23-year-old footballer!
The patient was discussed with orthopaedics, discharged from the ED with a Zimmer Splint and was made non-weight bearing. A week later they underwent knee arthroscopy and repair of the tibial spine/ACL. The meniscus was intact.
References and Further Reading:
- Davis DS, Post WR. Segond fracture: lateral capsular ligament avulsion. J Orthop Sports Phys Ther. 1997 Feb;25(2):103-6. doi: 10.2519/jospt.19184.108.40.206. PMID: 9007767.
- Shaikh H, Herbst E, Rahnemai-Azar AA, Bottene Villa Albers M, Naendrup JH, Musahl V, Irrgang JJ, Fu FH. The Segond Fracture Is an Avulsion of the Anterolateral Complex. Am J Sports Med. 2017 Aug;45(10):2247-2252. doi: 10.1177/0363546517704845. Epub 2017 May 12. PMID: 28499093.
- Arneja SS, Furey MJ, Alvarez CM, Reilly CW. Segond fractures: not necessarily pathognemonic of anterior cruciate ligament injury in the pediatric population. Sports Health. 2010 Sep;2(5):437-9
Filbay SR, Grindem H. Evidence-based recommendations for the management of anterior cruciate ligament (ACL) rupture. Best Practice & Research Clinical Rheumatology. 2019 Feb;33(1):33–47.
Dr Luke Phillips is an Emergency Physician at Alfred Health in Melbourne and currently the Co-Director of Emergency Medicine Training. He is a passionate educator and has been fortunate enough to be able to combine this with his love of emergency ultrasound.
Luke has a special interest in the use of focused ultrasound for critically unwell patients, in trauma management and in the use of ultrasound to guide procedures and improve patient safety in the ED. He is currently the Co-Chair of the Emergency Medicine Ultrasound Group (EMUGS.org) Board of Directors and holds a number of CCPU units through ASUM.
Luke is also involved in the department’s international education program and has developed a Certificate of Emergency Medicine which is currently being run in both Germany and India. He also has interests in human factors, debriefing (particularly after clinical events), and simulation.
His Twitter handle is @lukemphillips.