Showing papers on "Patella fracture published in 1992"

Incidence, mechanism of injury, and treatment of fractures of the patella in children.

Abstract: Fractures of the patella in skeletally immature patients are rare. The charts of 185 patients treated for patella fractures at the University of Kentucky Medical Center between 1976 and 1988 were retrospectively reviewed. The 12 patients of these 185 aged 8 to 16 years were included in this study. The incidence was calculated to be 6.5% of all patella fractures. All patients studied were male with an average age of 12.7 years. Sleeve fractures were the most common type of patella fracture observed (five), followed by transverse fractures (four). Ten of the 12 cases required operative management ranging from irrigation and debridement to open reduction and internal fixation. Partial patellectomy was performed when indicated. Indications for operative management in this age group were similar to those for adults. As in adults, the mechanism of injury was predominantly motor vehicle and motorcycle crashes. Laws requiring seatbelt restraints for children should have a positive effect on the incidence of such fractures resulting from dashboard injuries. One mechanism of injury not reported previously was that of a flexed knee striking the gym wall after performing a basketball lay-up because the basket was placed flush with the wall.

Posterior dislocation of total knee arthroplasty.

Abstract: Posterior dislocation of the prosthesis after total knee arthroplasty is an infrequent but serious complication. Seven patients with this complication were treated from January 1985 until October 1989. Five of the seven dislocations occurred in primary total knee arthroplasties and two occurred after revision arthroplasty. Limb alignment before arthroplasty, when it could be determined, was valgus in all patients, averaging 25 degrees. In each case there was an identifiable problem with the knee extensor mechanism: five had patellar dislocations, one a patellar tendon rupture, and one a patellar fracture. In three of the posterior dislocations, there was also an imbalance of the flexion and extension gaps with excessive laxity of the ligaments in flexion. Treatment was individualized. In two patients, the knee was reduced closed and the patella subsequently tracked so that no reoperation was necessary. One ruptured patellar tendon could not be repaired in a 94-year-old patient with cardiac disease. A cylinder cast was applied with poor results. Operative intervention was required in four patients, one of whom required only a patellar realignment procedure. The three other patients required component revision procedures, however, in addition to patellar realignment procedures. In these three patients, laxity of the knee in flexion was so severe that posterior instability could not be corrected merely by patellar relocation. At a follow-up examination (average, 21 months postoperatively), all six patients who were treated as recommended had good results with no further dislocations, with the exception of the one patient with a patellar tendon rupture.

Patellar complications after knee arthroplasty: A prospective study of 56 cases using the Kinematic prosthesis

Abstract: A prospective study on 56 knees was performed to analyze the incidence and cause of patellar complications following total knee arthroplasty with the Kinematic prosthesis inserted with the Universal Instrumentation system. Patellar complications occurred in 23 cases: 15 had anterior knee pain. There was 1 case of patellar fracture. Subluxation of the patella occurred in 13 cases, of which 6 were painful. Although the mechanical alignment was correctly reconstructed to neutral in all but 2 cases, the instrumentation tended to allow malpositioning of the components into excessive femoral valgus and compensatory excessive tibial varus that predisposed to patellar subluxation.With this prosthesis and instrumentation, patellar stability is hindered by a very short anterior femoral flange, a shallow patellar groove, and insertion of the components at 3° to the mechanical axis. It should be ensured that the components are correctly positioned, that patellar stability is carefully checked before closing the capsu...

Clinical and radiographic features, treatment and outcome in 15 horses with fracture of the medial aspect of the patella.

Abstract: A sagittal fracture of the medial aspect of the patella was identified in 15 horses, 2 of which had been kicked and 12 of which had hit a fixed fence while jumping. Eight horses showed concurrent fragmentation of the base of the patella, and 2 had sustained a concurrent fracture of the distal end of the lateral trochlear ridge of the femur. A cranioproximal-craniodistal oblique radiographic view was essential to identify the site of the medial patellar fracture and to determine its configuration. Fourteen horses were treated by surgical removal of the medial patellar fracture fragment(s). Of 12 horses (83%) without evidence of pre-existing degenerative joint disease, 10 were treated successfully with return to full athletic function.

Patella clamping device

Abstract: The utility model relates to a patella clamping device, which is an automatic reposition and fixation instrument for patellar fracture and comprises a fixing plate 1, two hollow supporters and a compression draw-rod 3 which are fixedly connected to the fixing plate 1, tension springs 6 arranged inside the hollow supporters, a sliding compression plate 4 sliding back and forth along the hollow supporters and the compression draw-rod, wire-needle fixing columns 7 respectively fixed to the fixing plate 1 and the sliding compression plate 4, wire-needles fixed to the fixing columns 7, etc. When the wire-needles are clamped at the ideal position of fracture, under the action of the tension spring, the fractured bone can be automatically restored to the original position and can be fixed. With scientific design, shapely configuration and moderate elastic force, the utility model has the double functions of automatic reposition and fixation of fracture.