Fixation Of Patellar Fractures Research Articles

Extensile exposure of comminuted patella fractures using a tibial tubercle osteotomy: results of a new technique.

To evaluate the clinical results of comminuted patella fracture fixation after an extensile surgical approach by using a tibial tuberosity osteotomy. Prospective, clinical. Six knees with displaced comminuted patella fractures had stable internal fixation after an osteotomy of the tibial tubercle. All had immediate postoperative continuous knee motion and were followed for an average of thirty-one months (minimum of eighteen months). Time to clinical and radiographic union, Hospital for Special Surgery (HSS) Knee Scores and comparisons with literature cohort studies. Clinical union of the osteotomy occurred at an average of eight weeks (range 6 to 12 weeks) and of the patella fractures at an average of eleven weeks (range 8 to 21 weeks). There was no radiographic evidence of osteotomy displacement, fracture implant loosening, migration, or failure. All patients had clinical residua, which included loss of motion, thigh muscle atrophy, and barometric complaints. HSS Knee Scores averaged 75 points with four good, one fair, and one poor result. These results were comparable to those of previously published reports of ablative surgery for this type of fracture. Comminuted patella fractures are severe injuries that usually result in some lingering morbidity. Internal fixation preserves bone stock, which facilitates future reconstructive procedures. The described tibial tuberosity osteotomy, patella eversion technique of fracture exposure improved visualization and reduction of the articular surface. The osteotomy healed in all cases and did not adversely affect the clinical results.

The use of non-absorbable suture in the fixation of patellar fractures: a preliminary report

We describe the use of a non-absorbable, braided, polyester suture, 5 Ti-Cron (Davis and Geck, Gosport, Hampshire), for the fixation of patellar fractures as an alternative to stainless steel wire. Seven patients had their fractures fixed with this material and all progressed to union with good restoration of knee function. The case of use of the suture allowed accurate reduction of the fractures and reduced operative and tourniquet time. None of the patients suffered significant complications from the procedure although two patients required removal of the suture because of knot symptoms. This was easily performed under local anaesthetic on an out-patient basis. We believe that non-absorbable suture is a good substitute for stainless steel wire and reduces the need for a second procedure for wire removal.

Evaluation of methods of internal fixation of transverse patella fractures: a biomechanical study.

Biomechanical testing was performed to evaluate five techniques of internal fixation of transverse patella fractures. Using cadaveric lower extremities, transverse osteotomies of the patella were performed, and the simulated fractures were fixed with the following techniques: the modified tension band, anterior tension band with a supplemental cerclage wire (the Pyrford technique), tension band with cancellous bone screws, Pyrford technique with cancellous screws, and cancellous screws alone. The fixation techniques were evaluated by measuring the separation of the fracture fragments during loading to produce a physiologic range of motion (90 degrees flexion to full extension). All techniques functioned adequately, with no fracture gap exceeding 1 mm. The tension band with screws technique performed significantly better than did the modified tension band, with an average fracture gap approximately half that of the traditional modified tension band technique. Mechanically, the addition of the screws to the tension band techniques reduces fracture separation by providing compression throughout the range of motion and by resisting the tensile loading during terminal extension.

Long-Term Results for the McKeever Patellar Resurfacing Prosthesis Used as a Salvage Procedure for Severe Chondromalacia Patellae

From July 1972 until September 1985, 28 patients with a mean age of 36 years who had advanced arthritis of the patella were treated with a resurfacing arthroplasty using the McKeever prosthesis. The opposing articular surface of the femur appeared normal in 19 patients. The 28 patients had had a total of 50 previous operations on the patella (average, 1.8 operations per patient). These included 15 arthroscopic or open debridements, 14 lateral releases, six Maquet tibial tubercle elevations, six open patellar ligament transpositions, and seven open procedures for reduction and fixation of patellar fractures. Every case was observed postoperatively from a minimum of four years to a maximum of 16 years (mean, 8.1 years). Results were evaluated according to a patellar rating scale at five and eight years postoperatively. Seventeen of 24 were rated good or excellent at five years. Of the three poor results at five years, two were attributed to tricompartmental osteoarthrosis and were revised to total knee arthroplasties. There were no significant complications in the series. No patients had postoperative patellar instability or prosthetic loosening. Prolonged physical therapy rehabilitation (mean, 4.6 months) was necessary for patients to regain maximal ranges of motion, muscle strength, and endurance.

Patellar Fixation Protected with a Load-Sharing Cable

The stability of patellar fracture fixation protected with a load-sharing cable was studied in cadavers. A transverse patellar osteotomy was produced and stabilized with standard patellar fixation with or without a figure-of-eight cable that extends from the proximal pole of the patella to the tibial tubercle. Standard fixation techniques (interfragmentary cancellous screws or modified tension-band wiring) alone failed after significantly fewer cycles of flexion and extension than did the same fixation when supplemented with a load-sharing cable. In the clinical evaluation of the load-sharing cable, 14 consecutive patients with displaced patellar fractures were treated. No immobilization was used and the patients were started on passive and active range of motion and weight-bearing ambulation in the early postoperative period. Thirteen fractures healed uneventfully. The increased stability of patellar fracture fixation protected with a load-sharing cable offers three advantages: (a) adjunctive casting is unnecessary, (b) comminuted fractures can be "pieced" together anatomically with less concern for loss of fixation, and (c) early postoperative passive and active range of motion can be achieved.

Biomechanical evaluation of various forms of fixation of transverse patellar fractures.

A study was undertaken to evaluate the strength and ease of application of four different forms of patellar fracture fixation. Modified tension band, screw fixation, Lotke longitudinal anterior band (LAB), and Magnusson wiring were examined using a Materials Testing System. Using cadaver lower extremities, the tibia was mounted in a fixed base and the tibiofemoral joint was fixed at 36 degrees. Tension was applied to the patella through the quadriceps tendon and fracture displacement was measured with linear motion transducers. Based on the results, we recommend screw fixation for transverse patellar fractures in patients with adequate bone stock. In patients with patellar fractures with comminution and/or osteopenia, modified tension band fixation is recommended. Simple wiring techniques alone may not provide sufficient fixation to allow immediate range of motion.