Avulsion Fracture

Plain radiographs provide many indications suggestive of acute ACL rupture avulsion fracture of the lateral tibial plateau, or Segond fracture, which is in fact an injury to the lateral joint capsule, avulsion of the Gerdy s tubercle and a lateral notch lesion, which is a compression fracture of the lateral femoral condyle of more than 2 mm seen on lateral radiograph. A tibial rim lesion on the posterolateral lip of the lateral tibial plateau can also be found alone or associated with the lateral notch lesion and is termed a kissing contusion. Joint effusions can also be detected on simple radiographs (Fig. 20.6). 

Furthermore, ACL tears are often associated with injuries to additional structures, such as the medial collateral ligament, meniscal tears, and Segond fracmres, which are capsular avulsion fractures of the lateral tibial plateau, found in 6-13 % of ACL ruptures [27] (Fig. 12.4C). 

Keywords Avulsion fracture Anterior cruciate ligament Open epiphyses... 

Avulsion fracture of the anterior cruciate ligament (ACL) is a fracmre of the tibial attachment site of the ACL, which is pulled out, rather than a tear in the substance of the ACL. It is also called an intercondylar eminence fracture of the tibia, tibial eminence fracture, tibial eminentia fracture, or tibial spine fracmre. Although a previous report suggested that ACL fibers could become elongated and damaged when avulsion fractures occur [1], the ACL substance is well preserved in most cases. Avulsion fractures of the ACL are seen in pediatric patients and infrequently in adult patients. Patients manifest symptoms similar to those of patients with ACL tears. Inadequate treatment can result in pain, range of motion limitation, and joint... 

Avulsion fracture of the ACL occurs during sports activities and traffic accidents. Generally, it is seen more often in children than in adults, most likely because the ACL attachment site on the bone is immature and biomechanically weak in children [2]. Avulsion fracture of the ACL often occurs in children between ages 6 and 17 years [3-5]. Previous reports have suggested that the mechanism of injury is direct force, with hyperextension of the knee and injury patterns similar to ACL tears [6-9]. 

Fig. 35.1 Classification of anterior cruciate ligament avulsion fractures...

Patients with avulsion fracture of the ACL usually exhibit swelling and hemarthrosis. Manual tests for detecting ACL injuries, such as the Lachman test and pivot shift test, can be positive. The Lachman test shows an unclear end point, as is usual with ACL injury, and the examiner will feel an increased anteroposterior translation of the tibia during the test. The pivot shift test may be difficult to perform because of pain in the acute phase. 

These biomechanical studies provided useful information in the surgical treatment choice for ACL avulsion fractures. However, the cadavers used in the reported studies were of advanced age, and the fracture models were not the same as the fractures seen in patients. Therefore, results may differ in patients. 

A number of clinical outcomes after treatment for ACL avulsion fractures in... 

Louis et al. treated 17 pediatric patients (age 6-16 years) with type II fractures by open reduction and internal fixation with sutures or a suture anchor. They reported that none of the patients showed obvious instability, and all patients were able to return to their original sports activities. The authors, therefore, recommended surgical treatment for type II tibial intercondylar eminence fractures in children [39]. Casalonga et al. retrospectively examined 32 children with avulsion fractures of the ACL, including 8 type I, 17 type II, 5 type III, and 2 type IV fractures, who were treated both conservatively and surgically, with a mean followup of 9 years. Type I and II fractures were treated conservatively, and types III and IV were treated by open reduction and fixation with either sutures or a screw. The mean side-to-side anteroposterior difference on KT-1000 testing was 0.88 mm for... 

My colleagues and I prefer to treat ACL avulsion fractures using a pullout suture technique under arthroscopy. We believe that the pullout suture technique can be applied in most cases, including those with comminuted fractures. Our surgical method is described below. 

Avulsion fracture of the ACL is one of the common injuries seen in children. Minimally displaced fractures can be treated conservatively, whereas displaced fragments should be reduced properly and fixed with careful attention to the epiphyseal plate. Various surgical methods have been reported, and surgerMis should know the advantages and disadvantages of each procedure. The prognosis for patients with avulsion fracture of the ACL is acceptable if proper treatments are applied. 

Song EK, Seon JK, Park SJ, Yoon TR (2009) Clinical outcome of avulsion fracture of the anterior cruciate ligament between children and adults. J Pediatr Orthop B 18 335-338. doi 10. 1097/BPB.0b013e32832f06bd... 

Lubowitz JH, Elson WS, Guttmann D (2005) Part II Arthroscopic treatment of tibial plateau fiactures intercondylar aninence avulsion fractures. Arthroscopy 21 86-92. doi 10.1016/j. arthro.2004.09.031... 

Lu XW, Hu XP, Jin C, Zhu T, Ding Y, Dai LY (2010) Reduction and fixation of the avulsion fracture of the tibial eminence using mini-open technique. Knee Surg Sports Traimiatol Arthrosc 18 1476-1480. doi 10.1007/s00167-010-1045-0... 

Hunter RE, Willis JA (2004) Arthroscopic fixation of avulsion fractures of the tibial eminence technique and outcome. Arthroscopy 20 113-121. doi 10.1016/j.arthro.2003.11.028... 

Huang TW, Hsu KY, Cheng CY, Chen LH, Wang CJ, Chan YS, Chen WJ (2008) Arthroscopic suture fixation of tibial eminence avulsion fractures. Arthroscopy 24 1232-1238. doi 10.1016/ j.arthro.2008.07.008... 

Su WR, Wang PH, Wang HN, Lin CJ (2011) A simple, modified arthroscopic suture fixation of avulsion fracture of the tibial intercondylar eminence in children. J Pediatr Orthop B 20 17-21. doi 10.1097/BPB.0bO13e32832d8452... 

In Y, Kim JM, Woo YK, Choi NY, Moon CW, Kim MW (2008) Arthroscopic fixation of anterior cruciate ligament tibial avulsion fractures using bioabsorbable suture anchors. Knee Surg Sports Traumatol Arthrosc 16 286-289. doi 10.1007/s00167-007-0466-x... 

Kwon OS, Kamath AF, Kelly JD (2012) Arthroscopic treatment of an anterior cruciate ligament avulsion fracture in a skeletally immature patient. Orthopedics 35 589-592. doi 10. 3928/01477447-20120621-04... 

Mann MA, Desy NM, Martineau PA (2012) A new procedure for tibial spine avulsion fracture fixation. Knee Surg Sports Traumatol Arthrosc 20 2395-2398. doi 10.1(X)7/s00167-012-1906-9... 

In Y, Kwak DS, Moon CW, Han SH, Choi NY (2012) Biomechanical comparison of three techniques for fixation of tibial avulsion fractures of the anterior cruciate ligament. Knee Surg Sports Traumatol Arthrosc 20 1470-1478. doi 10.1007/s00167-011-1694-7... 

Tsukada H, Ishibashi Y, Tsuda E, Hiraga Y, Toh S (2005) A biomechanical comparison of repair techniques for anterior cruciate ligament tibial avulsion fracture under cyclic loading. Arthroscopy 21 1197-1201. doi 10.1016/j.arthro.2005.06.020... 

Prince AR, Moyer RA (1995) Arthroscopic treatment of an avulsion fracture of the intercondylar eminence of the tibia. Case report. Am J Knee Surg 8 114—116... 

Tudisco C, Giovarruscio R, Febo A, Savarese E, Bisicchia S (2010) Intercondylar eminence avulsion fracture in children long-term follow-up of 14 cases at the end of skeletal growth. J Pediatr Orthop B 19 403 08. doi 10.1097/BPB.0b013e32833a5f4d... 

Sleeve avulsion fractures are a particular form of avulsion injury seen in the unossified skeleton which differs from avulsions in adults because the sleeve of periosteum which is pulled off can continue to form bone if not treated. The typical location is at the lower pole of the patella, but the upper pole of the patella, the olecranon and the medial epicondyle can also be affected. Ultrasound demonstrates a sleeve of cartilage that has been avulsed usually with a small fragment of bone (Hunt and Somashekar 2005). In some cases a double cortical sign may be present, indicating elevation of a superficial layer of cortex from the underlying bone. There maybe associated haemarthrosis and patella alta (Fig. 4.14). 

Rupture of the superior peroneal retinaculum, which extends from the lateral aspect of the distal fibular to the calcaneus, may result in peroneal tendon subluxation. Sometimes there is an associated avulsion fracture of the lateral aspect of the distal fibula. Typically, the patient will complain of painful clicking of the ankle, particularly on dorsiflexion and eversion of the foot. The diagnosis is often obvious... 

C2 develops from four ossification centres at birth, one for each neural arch, one for the body and one for the odontoid process. The odontoid process itself forms from two separate ossification centres that fuse in the midline by the 7 fetal month, but occasionally can persist as a vertical lucent cleft in the odontoid (Ogden 1984). A secondary ossification centre appears at the tip of the odontoid process between 3 and 6 years of age and fuses by 12 years. This can be mistaken for an avulsion fracture (Fig. 7.57). The body of C2 fuses with the odontoid process by 2-6 years leaving a fusion line or remnant of the cartilaginous synchondrosis until 11 years of age and may be confused with a fracture either on radiographs or CT (Fig. 7.58). Pseudofractures of the odontoid process can be produced by the Mach effect by overlapping of the teeth, the posterior arch of Cl, occiput or soft tissues such as the tongue (Fig. 7.59). The neural arches of C2 fuse posteriorly by 2-3 years of age and the body fuses with the neural arches by 3-6 years. Additional ossification centres may be found at the tips of the spinous... 

Avulsion fractures are more common in adolescents and are associated with a better outcome and less complications. 

Avulsion fractures of the posterior inferior iliac spine and the transverse process of the 5 lumbar vertebra are rare but indicative of severe trauma. The former occurs as a result of external rotation of the hemi-pelvis which avulses the sacrospinous ligament at its insertion. The latter injury results when the ilio-lumber ligament is avulsed from the tip of the transverse process of L5 by shearing forces in the vertical plane. These injuries should arouse suspicion of pelvic instability. 

These are incomplete fractures with no disruption of the pelvic ring. Type A1 are avulsion fractures which commonly occur in athletic teenagers. The avulsion may be from the anterior-superior iliac spine, caused by sudden contraction of Sartorious, anterior-inferior ischial spine (rectus femoris insertion), and the pubic tubercle (pectineus insertion). 

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