Inferior sleeve fracture of the patella

Abstract

Patella sleeve fracture is a rare fracture that only occurs in children. Diagnosis is difficult both clinically and radiologically. A high-riding patella and hemarthrosis are important signs when diagnosing this fracture. We report a case of an 11-year-old boy who suffered from patella sleeve fracture without visible bony fragments on a lateral radiograph. Open reduction with transosseous tunneling and patellotibial cerclage wiring for anastomosis protection was performed. Early weight bearing was achieved together with a satisfactory range of knee motion. Premature anterior physeal arrest was noted because of insertion of cerclage wire in the open physis. However, no genu recurvatum was present 2 years after the initial operation. An awareness of sleeve fracture, together with its characteristic clinical and radiological features, is important to avoid misdiagnosis and treatment delay. If the cerclage wire technique is used, care should be taken not to disturb the proximal tibial apophysis.

Patellar Sleeve Fracture in an Eight-Year-Old Girl

“…Initially, the diagnosis may be demanding and difficult, depending on both clinical and radiographic evidence deducted from physical examination, and critical analysis of the X-rays [8]. Unlike this case, where an osseous fragment was found detached from the distal pole of the patella, most patellar sleeve fractures lack this radiographic sign, and diagnosis only depends on having a high-riding patella or patella alta on the lateral plain radiograph.…”

“…Patellar height is measured by the Insall-Salvati ratio, which is the length of the patellar ligament divided by patellar length on lateral X-rays. The mean ratio is 1.04 in adults (1.01 in males and 1.06 in females), with patella alta having an Insall-Salvati ratio of >1.2, and patella Baja having a ratio of <1.0 [8].…”

Sleeve fracture of the patella with lateral slip of the retinaculum

“…There are few case reports on sleeve fractures available in the literature [2,3,5,6,8,9,13,15], but they all describe inferior or superior pole fractures; however, all the previous authors have also emphasized an early diagnosis and prompt surgical intervention of such injuries. Guy et al [2] described a case of bilateral sleeve avulsion fractures of the lower poles of the patellae in an 11-yearold boy following an indirect trauma to both knees.…”

“…They showed satisfactory functional rehabilitation on long-term follow-up of these children aged between 9 and 15 years. Lin et al [5] reported a case of an 11-year-old boy who sustained a patellar sleeve avulsion fracture of the lower pole. Cerclage wire was used to augment the repair in this case; however, this resulted in premature growth arrest because of the wire going through an open physis.…”

“…A sleeve fracture is defined as an avulsion of a small bony fragment from the distal or proximal pole of the patella, along with its articular cartilage, periosteum, and retinaculum, which is pulled off from the main body of the patella in the coronal plane [2]. This type of fracture accounts for almost half of all the patellar fractures in this age group [1,[3][4][5]. Adolescents are the most susceptible, probably because of the intensity of sporting activity, rapid growth with osteochondral transformation at the periphery of the patella, and relative patellar mobility [4].…”