Traumatic Knee Pain

Abstract

[Ann Emerg Med. 2009;53:403.] A 19-year-old man presented after riding a 125-cc dirt bike. While accelerating, the bike slipped out from underneath him, and he fell onto his left side. He presented with pain in his left knee after his flexed knee went into extreme varus alignment. His physical examination result was notable for diffuse left knee swelling, ecchymosis of medial knee, and a large intraarticular knee effusion. Patellar apprehension test result was negative, and the Lachman's test result was positive. Knee motion was limited from –8 to 60 degrees of flexion. There was a firm endpoint with posterior drawer testing at the above mentioned flexion angle. The remainder of the ligamentous knee examination was limited as a result of pain and guarding. Radiographs were obtained (Figure 1). The Segond fracture is a small vertical avulsion injury of the lateral aspect of the proximal tibia immediately distal to the tibial plateau. The mechanism of injury is an axial load on a semiflexed knee, with internal rotation and varus stress.1Davis D.S. Post W.R. Segond fracture: lateral capsular ligament avulsion.J Orthop Sports Phys Ther. 1997; 25: 103-106Crossref PubMed Scopus (35) Google Scholar, 2Irvine G.B. Dias J.J. Finlay D.B.L. Segond fractures of the lateral tibial condyle: brief report.J Bone Joint Surg. 1987; 69-B: 613-614Google Scholar The fracture has a strong association with an anterior cruciate ligament tear (75% to 100%), as well as meniscal injury (67% to 75%)3Dietz G.W. Wilcox D.M. Montgomery J.B. Segond tibial condyle fracture: lateral capsular ligament avulsion.Radiology. 1986; 159: 467-469PubMed Google Scholar, 4Goldman A.B. Pavlov H. Rubenstein D. The Segond fracture of the proximal tibia: a small avulsion that reflects major ligamentous damage.AJR Am J Roentgenol. 1988; 151: 1163-1167Crossref PubMed Scopus (172) Google Scholar, 5Bathala E.A. Bancroft L.W. Ortiguera C.J. et al.Radiologic case study Segond fracture.Orthopedics. 2007; 30 (688): 689PubMed Google Scholar, 6Weber W.N. Neumann C.H. Barakos J.A. et al.Lateral tibial rim (Segond) fractures: MR imaging characteristics.Radiology. 1991; 180: 731-734PubMed Google Scholar (Figure 2). A hemarthrosis is commonly present.3Dietz G.W. Wilcox D.M. Montgomery J.B. Segond tibial condyle fracture: lateral capsular ligament avulsion.Radiology. 1986; 159: 467-469PubMed Google Scholar Clinically, signs of anterior instability such as a positive pivot-shift test result, Lachman's test, and anterior draw sign may be present.5Bathala E.A. Bancroft L.W. Ortiguera C.J. et al.Radiologic case study Segond fracture.Orthopedics. 2007; 30 (688): 689PubMed Google Scholar The most specific clinical test is the pivot-shift test, but false-negative results may occur from a locked knee or guarding.4Goldman A.B. Pavlov H. Rubenstein D. The Segond fracture of the proximal tibia: a small avulsion that reflects major ligamentous damage.AJR Am J Roentgenol. 1988; 151: 1163-1167Crossref PubMed Scopus (172) Google Scholar Furthermore, physical examination (Lachman's and anterior draw test) to evaluate the function of the anterior cruciate ligament may be unreliable as result of pain, hamstring resistance, or effusion.7Kerr H.D. Segond fracture, hemarthrosis, and anterior cruciate ligament disruption.J Emerg Med. 1990; 8: 29-33Abstract Full Text PDF PubMed Scopus (10) Google Scholar Radiographically, the bone fragment is located on the lateral edge of the tibial condyle and is best visualized on the anterior-posterior view. The Segond fragment, seen on plain radiograph, is identified by magnetic resonance imaging only in one third of cases.6Weber W.N. Neumann C.H. Barakos J.A. et al.Lateral tibial rim (Segond) fractures: MR imaging characteristics.Radiology. 1991; 180: 731-734PubMed Google Scholar Although magnetic resonance imaging is not sensitive in the detection of the Segond fracture fragment, it is useful in demonstrating associated ligamentous and meniscal injuries.6Weber W.N. Neumann C.H. Barakos J.A. et al.Lateral tibial rim (Segond) fractures: MR imaging characteristics.Radiology. 1991; 180: 731-734PubMed Google Scholar Management entails elevation, ice application, crutches, knee immobilization, and prompt orthopedic referral.7Kerr H.D. Segond fracture, hemarthrosis, and anterior cruciate ligament disruption.J Emerg Med. 1990; 8: 29-33Abstract Full Text PDF PubMed Scopus (10) Google Scholar Consideration should be given to drainage of tense effusions for pain relief.