Patellar fracture after total knee arthroplasty

BACKGROUND: Patellar fracture can occur as a complication following total knee arthroplasty. The purpose of this study was to evaluate a large series of patellar fractures to determine the results of different forms of treatment of specific fracture types. METHODS: A retrospective review identified eighty-five fractures (in seventy-seven patients) following 12,464 consecutive total knee arthroplasties performed between 1985 and 1998. Seventy-eight fractures occurred after primary total knee arthroplasty and seven, after revision total knee arthroplasty. Five fractures were treated elsewhere, and two others were lost to follow-up. The results of treatment of the remaining seventy-eight fractures were reviewed. Fractures were classified according to three main criteria: integrity of the extensor mechanism, fixation status of the patellar implant, and quality of the remaining bone stock. The mean duration of follow-up was 3.6 years. RESULTS: The prevalence of patellar fracture after total knee arthroplasty was 0.68%; fractures were significantly more prevalent among men (1.01%) than among women (0.40%) (p = 0.0004). Thirty-eight fractured patellae had a stable implant and an intact extensor mechanism (Type I). All but one were treated nonoperatively, and there was only one late failure of nonoperative treatment, which required operative intervention. Twelve fractures were associated with disruption of the extensor mechanism (Type II). Eleven were treated operatively; six knees had complications and five had a reoperation. Twenty-eight fractures occurred in association with a loose patellar component (Type III). Twenty were treated operatively; nine knees had complications, and four had a reoperation. CONCLUSIONS: Patellar fractures after total knee arthroplasty are infrequent. Treatment can be guided by three main criteria: integrity of the extensor mechanism, fixation status of the patellar implant, and quality of the remaining bone. Fractures associated with a stable implant and an intact extensor mechanism were usually treated successfully with nonoperative means, with minimal complications. When operative treatment was required, it was associated with a high rate of complications and reoperations.     

The results of treatment of supracondylar fracture above total knee arthroplasty

This study analyzes the results of treatment of 22 patients with 24 supracondylar femur fractures above a total knee arthroplasty. Ten knees were treated by closed methods utilizing traction and then a cast, 10 knees with immediate open reduction and internal fixation, 2 knees with a custom total knee integrated with a distal femoral allograft, 1 knee with external fixation, and 1 knee with primary arthrodesis. Nine fractures treated by closed means and 5 fractures treated by open reduction and internal fixation healed primarily. Two of the 5 surgical failures healed after replating and bone graft. The 3 failures of surgical therapy were salvaged utilizing custom total knee arthroplasty, 2 of which required integration with a distal femoral allograft. One knee treated with external fixation developed a deep infection necessitating implant removal and arthrodesis. Twelve of the 14 femoral fractures that united primarily healed with the femoral component in varus with respect to the long axis of the anatomic femur. Nine of these 12 implants developed progressive radiolucent lines at the tibial component. Three of these knees have required implant revision due to progressive loosening of the tibial and/or femoral components. The results of this evaluation indicate that fractures above a well-fixed total knee arthroplasty are difficult to manage. If anatomical alignment cannot be achieved by simple closed techniques, then primary open reduction and internal fixation should be considered. However, because of the complexity of the problem, the surgeon should be prepared to perform a primary arthrodesis or revision using custom components with or without a distal femoral allograft.     

Treatment of supracondylar fractures following prosthetic arthroplasty of the knee

Fifteen supracondylar fractures of the femur in patients with ipsilateral total knee arthroplasties were treated between 1975 and 1982. Three groups were identified for analyzation of treatment and end result. The average follow-up period after fracture was 18 months, with a range of ten to 48 months. Group I had four patients treated by closed reduction, cast immobilization, and early weight-bearing. At follow-up evaluation, three had a decrease in knee rating score, and one required a corrective osteotomy. Group II had eight patients treated by traction followed by cast or cast-brace immobilization. Four patients had a decrease in the knee rating because of malunion or loss of motion, and there was one nonunion requiring surgical treatment. Group III had three patients treated by immediate open reduction and internal fixation of the fracture. All three groups had functional arthroplasties following union of the fracture. Closed reduction and skeletal traction are recommended for the initial treatment. Open reduction and internal fixation, when technically feasible, is recommended when closed reduction and skeletal traction cannot maintain satisfactory alignment.     

Anterior femoral notching and ipsilateral supracondylar femur fracture in total knee arthroplasty

The authors reviewed 670 total knee arthroplasties with a 2-10-year follow-up period. Of these, 180 knees had anterior femoral notching, which was deeper than 3 mm in 138. Two of the 670 knees suffered ipsilateral supracondylar fractures; one of these had a notched femur and one did not. Both fractures occurred at the anterior patellar flange-bone junction. No correlation was found between anterior femoral notching and ipsilateral supracondylar femur fracture.     

Interprothetische Frakturen am Femur

The treatment of interprosthetic fractures is challenging and the incidence is increasing as a result of increasing patient longevity and rising arthroplasty rates. Interprosthetic fractures occur between arthroplasty stems or any intramedullary implant that has been implanted for fracture fixation. Management of these fractures is a complex undertaking. The majority of fractures are localized at the femoral supracondylar level after knee resurfacing arthroplasty. The fixation status of the arthroplasty component determines the management strategies. As a result of clinical and biomechanical studies, loosening of the implant usually requires revision arthroplasty, whereas minimally invasive reduction and locked internal fixation is the treatment of choice for stable implants. Minimally invasive surgery is necessary to not further compromise local perfusion. As locked plating provides superior biomechanical stability, the use of cerclage cables should be carefully evaluated. Complex fracture configurations, inferior bone stock or an intramedullary canal that is already occupied by support structures might obviate the implantation of long revision stems and might require a more extensive approach (e.g., total femoral arthroplasty).     

A new method of treatment for periprosthetic supracondylar fractures of the femur for prostheses with a stemmed femoral component

Knee arthroplasty periprosthetic supracondylar fracture of the femur is a well-recognized problem that is likely to be seen more frequently with the increasing number of knee arthroplasties being performed. Treatment of this fracture is difficult. A new method of internal fixation for supracondylar fractures around a stemmed femoral component using a custom-made extension to the femoral stem is described. This technique allowed early mobilization of the patient, with restoration of a good range of movement of the knee and fracture union within 1 year.     

Long-term Survival Rate of Implants and Modes of Failure After Revision Total Knee Arthroplasty by a Single Surgeon

The purpose of the present study was to analyze the survival rate of implants and mode of failure after revision total knee arthroplasty (TKA) using one type of modular prosthesis by a single surgeon. From September 1990 to June 2009, 224 revision TKAs were performed in 194 patients. The 5-, 8-, and 10-year survival rates were 97.2%, 91.6%, and 86.1%, respectively. Re-revision TKAs were performed in 20 knees because of infection (seven knees), loosening (six knees), polyethylene wear (six knees), and periprosthetic fractures (one knee). The long-term survival rate of revision TKA was satisfactory, but careful attention is necessary to detect the late failure. The prevention of infection and the stable fixation of components are required at the time of revision TKA.     

The modular segmental kinematic rotating hinge for nonneoplastic limb salvage

From January 1980 to July 1998, 25 patients (26 knees) were treated with an arthroplasty using a Modular Segmental Kinematic Rotating Hinge total knee prosthesis for nonneoplastic limb salvage. The indications included: nonunion of a periprosthetic femur fracture (11 knees), severe bone loss and ligamentous instability (eight knees), nonunion of a supracondylar femur fracture (four knees), acute periprosthetic fracture (one knee), fracture of a previous hinge (one knee), and prior resection arthroplasty (one knee). The average age of the patients was 72.3 years. Twenty-two arthroplasties were revisions. The average followup was 58.5 months. At the latest followup, knee extension averaged 2.4 degrees and flexion averaged 93.6 degrees. The Knee Society knee score improved from an average of 45.4 preoperatively to 75.5. Preoperatively, functional scores averaged 8.6 and improved to 25. Complications occurred in eight patients. The most common was deep infection (five patients). The use of the Modular Kinematic Rotating Hinge for nonneoplastic limb salvage represents a small proportion (0.14%) of all primary and revision knee arthroplasties done at our institution. The indications for the surgery are for a highly complex and small subset of patients. The patients in the current study gained significant improvement in overall range of motion, Knee Society knee scores, and functional scores when this prosthesis was used.     

The effect of alignment of the implant on fractures of the patella after condylar total knee arthroplasty

The results in thirty-six knees that had a fracture of the patella after a total condylar arthroplasty were reviewed, and were analyzed according to the type of fracture and the alignment of the implant and the limb. Most of the fractures occurred two years or less after the initial operation. Fourteen knees were rated fair or poor and twenty-two, good or excellent. None of the thirty-six implants had been aligned in the neutral range. In sixteen knees, the alignment had a minor variation from the neutral range--that is, the knees were in minor malalignment. In general, these knees had the least severe fractures and the best over-all results. All had a good or excellent result except one, which was revised because of a loose patellar component. That knee was rated as fair at the latest follow-up. There was a major discrepancy in the alignment of twenty implants. These knees had more severe fractures and less satisfactory results than those in the other group. In two of these knees, the fracture was treated non-operatively; one had a good and the other, a poor result. Twelve of the remaining knees, which were treated surgically, were rated as fair or worse. Two knees that had revision of three components and restoration of alignment to the neutral range had an excellent result. The results of this study indicate that the alignment and fit of a component are important in determining the severity of a fracture of the patella after condylar total knee replacement and the long-term results after treatment of the fracture.     

Supracondylar distal femoral nonunions treated with a megaprosthesis in elderly patients: a report of two cases.

The purpose of this paper is to report the use of total knee arthroplasty, a megaprosthesis, as a treatment in elderly patients who have a persistent nonunion of a supracondylar femur fracture. This case report includes two elderly patients who sustained supracondylar femur fractures that failed to unite with standard operative fixation methods. Despite multiple procedures during a long period, patients had a persistent nonunion. Both patients underwent total arthroplasty with a cemented kinematic rotating hinge and had significant clinical improvement. The Hospital for Special Surgery (HSS) knee scores increased from fifty-four points to seventy points in one patient and forty-two points to seventy-three points after surgery in the other patient. Both patients had excellent range of motion after surgery. A cemented megaprosthesis appears to be a viable treatment option for persistent nonunions of supracondylar femur fractures in elderly patients. It is well tolerated and permits early ambulation and return to activities of daily living.     

Impaction grafting and wire mesh for uncontained defects in revision knee arthroplasty

The current authors review the results of 17 revision total knee arthroplasties in 14 patients in whom large uncontained defects were treated with impaction allografting and molded wire mesh for containment. Knee Society clinical scores increased from an average of 47 points to 95 points and function scores increased from 48 points to 73 points at the most recent followup. No patients required revision surgery, although, nonprogressive tibial radiolucency has been observed in three patients. One patient required open reduction and internal fixation of a periprosthetic supracondylar femur fracture. One patient with an acute postoperative infection with Staphylococcus epidermidis was treated successfully with irrigation and debridement with retention of the implant. Impaction grafting with wire mesh containment for large uncontained defects in revision total knee arthroplasty is an effective method of treating massive uncontained bone loss in revision total knee arthroplasty.     

Periprothetische Frakturen nach Knietotalendoprothetik

The increasing implantation rates of knee arthroplasties are associated with a growing prevalence of complications like periprosthetic fractures. Underlying patient, implant and/or operation technique-related risk factors contribute to these fractures which often occur after minor trauma. In the diagnostic process, fracture dislocation, implant stability, and integrity of the extensor mechanism have to be assessed. Valid classification systems are available to guide treatment decisions. Treatment goals are precise reposition, stable fixation, restoration of function, and early mobilization. In the case of an operative revision, the surgeon has to know the implanted device and has to be prepared for extended procedures and revision arthroplasty. Less invasive fixation devices like retrograde nailing or LISS are often sufficient to stabilize femoral supracondylar fractures, while loosening of the implant often requires extended exchange arthroplasty. Tibial fractures are often associated with osteolysis and bone loss which has to be addressed with bone grafts or augmented revision implants. Long-stemmed implants allow bypassing of the reconstructed defect and provide a stable solution for early mobilization. Patella fractures with stable or asymptomatic implants and continuity of the extensor mechanism should be treated conservatively. If reconstruction becomes necessary, results are often associated with significant functional limitations.     

Periprosthetic fractures after total knee arthroplasty

The increasing implantation rates of knee arthroplasties are associated with a growing prevalence of complications like periprosthetic fractures. Underlying patient, implant and/or operation technique-related risk factors contribute to these fractures which often occur after minor trauma. In the diagnostic process, fracture dislocation, implant stability, and integrity of the extensor mechanism have to be assessed. Valid classification systems are available to guide treatment decisions. Treatment goals are precise reposition, stable fixation, restoration of function, and early mobilization. In the case of an operative revision, the surgeon has to know the implanted device and has to be prepared for extended procedures and revision arthroplasty. Less invasive fixation devices like retrograde nailing or LISS are often sufficient to stabilize femoral supracondylar fractures, while loosening of the implant often requires extended exchange arthroplasty. Tibial fractures are often associated with osteolysis and bone loss which has to be addressed with bone grafts or augmented revision implants. Long-stemmed implants allow bypassing of the reconstructed defect and provide a stable solution for early mobilization. Patella fractures with stable or asymptomatic implants and continuity of the extensor mechanism should be treated conservatively. If reconstruction becomes necessary, results are often associated with significant functional limitations.     

Total knee arthroplasty after open reduction and internal fixation of fractures of the tibial plateau: a minimum five-year follow-up study

BACKGROUND: There is little information in the literature regarding the outcome of total knee arthroplasty following open reduction and internal fixation of fractures of the tibial plateau. The goal of this study was to evaluate the results of such procedures after a minimum of five years of follow-up. METHODS: We retrospectively analyzed the outcomes of fifteen total knee arthroplasties performed at an average of 38.6 months (range, eight months to eleven years) after open reduction and internal fixation of a fracture of the tibial plateau in fifteen consecutive patients. The average duration of follow-up after the total knee arthroplasty procedures was 6.2 years (range, 5.4 to 11.1 years). The average age of the patients was fifty-six years (range, thirty-seven to sixty-eight years) at the time of the arthroplasty. We evaluated the outcomes on the basis of the Hospital for Special Surgery knee score, the Short Form-36 score, and radiographs of the knees. RESULTS: The average Hospital for Special Surgery knee score was 51 points (range, 20 to 74 points) before the arthroplasty, and it increased to 80 points (range, 44 to 91 points) postoperatively. Four knees were scored as excellent, eight had a good result, one was rated as fair, and two had a poor result. The average Short Form-36 scores were 58.0 points for general health, 72.4 points for bodily pain, 72.1 points for mental health, 58.3 points for physical functioning, 84.6 points for physical role functioning, 81.0 points for social functioning, and 57.7 points for vitality. The average active postoperative arc of motion was 105 degrees (range, 70 degrees to 135 degrees ) compared with 87 degrees (range, 20 degrees to 125 degrees ) preoperatively. Incomplete radiolucencies were noted on all of the postoperative radiographs made after the total knee arthroplasties. There was a high rate of infection (three patients), patellar tendon disruption (two patients), and postoperative secondary procedures (three patients required closed manipulation). The patients with infection were considered to have a failure of treatment: two required arthrodesis, and one required a two-stage exchange. CONCLUSION: On the basis of our results, we concluded that total knee arthroplasty after open reduction and internal fixation of a fracture of the tibial plateau decreases pain and improves knee function, but the procedure is technically demanding and is associated with a high failure rate (five of fifteen).     

The kinematic rotating hinge prosthesis for complex knee arthroplasty.

Fifty-eight patients (69 knees) treated with the Kinematic Rotating Hinged knee prosthesis for complex primary and salvage revision total knee arthroplasty were followed up for an average of 75.2 months (range, 24-199 months). The indications for use of the Kinematic Rotating Hinged knee prosthesis included severe bone loss combined with ligamentous instability (30 knees), nonunion of a periprosthetic fracture (10 knees), an acute periprosthetic fracture (nine knees), severe collateral ligamentous instability (five knees), reimplantation for infection (six knees), nonunion of a supracondylar femoral fracture (four knees), congenital dislocation of the knee (three knees), and treatment of a severely comminuted distal femur (two knees). At the time of surgery, the average patient age was 72 years (range, 46-92 years). Preoperatively, knee extension averaged 4.94 degrees (range, 0 degrees-40 degrees) and flexion averaged 81 degrees (range, 15 degrees-125 degrees). At final followup, knee extension averaged 1.25 degrees (range, -5 degrees-25 degrees) and flexion averaged 94.2 degrees (range, 5 degrees-125 degrees). The preoperative Knee Society Knee score averaged 40.3 points (range, 2-93 points) and improved to 77 points (range, 33-99 points) at final followup. Complications were numerous: 23 (32%) patients experienced at least one complication and 12 (17%) patients had two or more complications. Deep periprosthetic infection was the most common complication (14.5%), followed by patellar complications (13%), and prosthetic component breakage (10%). During the period of this study, there were 15,798 primary and 2673 revision total knee arthroplasties done at the authors' institution. The patients receiving a Kinematic Rotating Hinged knee prosthesis represent a highly complex and small subset (0.37%) of the overall population having knee arthroplasty. Although the use of the Kinematic Rotating Hinged knee prosthesis for these limited indications has been useful for the authors, the incidence of complications and the poor outcome of these complications is disconcerting. Hinged total knee arthroplasty should be reserved for the final salvage option of the treatment options available when doing complex primary and salvage revision knee arthroplasties.     

Simultaneous revision and contralateral primary total knee arthroplasty

BACKGROUND: There is controversy regarding whether simultaneous or staged bilateral total knee arthroplasty should be performed in patients with bilateral gonarthrosis. In addition, revision total knee arthroplasties have been less successful than primary arthroplasties. The purpose of this study was to evaluate the results of simultaneous revision and contralateral primary total knee arthroplasties performed during the same setting. METHODS: The study cohort included 150 knees in seventy-five patients who had undergone revision arthroplasty because of aseptic failure of a total knee arthroplasty and a contralateral primary arthroplasty for severe gonarthrosis under the same anesthetic. The study group was compared with a control group of sixty patients who had severe arthritis in one knee and had undergone unilateral revision total knee arthroplasty on the contralateral side. The duration of follow-up averaged five years in the group treated with the simultaneous arthroplasties and eight years in the control group. Clinical and radiographic results were evaluated with the Knee Society rating system. RESULTS: In the study group, the average knee score improved by 48 points on the side of the primary arthroplasty and by 37 points on the side of the revision. At the last follow-up visit, most (sixty-five) of the seventy-five patients stated that the knee with the revision felt better than the knee with the simultaneously performed primary arthroplasty. In the control group, the average knee score improved by 30 points on the side of the revision arthroplasty. However, forty-five of the sixty patients had a primary total knee arthroplasty on the contralateral side within two years after the index revision arthroplasty; by four years, all sixty patients had undergone a contralateral primary arthroplasty. CONCLUSIONS: We found a favorable outcome in patients who had undergone simultaneous revision and contralateral primary total knee arthroplasties. Despite a lower mean knee score and less motion, most patients seemed to prefer the knee with the revision arthroplasty to the knee with the primary procedure. These results suggest that this combined procedure is a safe and favorable alternative to a staged procedure consisting of revision and subsequent contralateral primary total knee arthroplasty.     

Total knee arthroplasty using the kinematic rotating hinge prosthesis

Patients receiving a Kinematic Rotating Hinge total knee prosthesis with a 25-month minimum follow up were reviewed. A total of 46 patients and 54 knees were included in the study. A detailed clinical assessment was available on 38 knees. Twenty of these knees had primary arthroplasties performed with the Kinematic Rotating Hinge prosthesis and 18 knees had revision arthroplasty. Ninety-five percent of primary knees and 83% of revision knees caused no or mild pain postoperatively. Using the Brigham and Women's Hospital and Harvard Medical School knee rating system, 80% of primary knees and 61% of revision knees were rated as good to excellent. Using the criteria defined in this article, 90% of primary knees and 83% of revision knees were labeled as having a satisfactory result. Forty-five percent of primary components and 52% of revision components demonstrated lucent lines on radiographic review. Seven percent of primary knees and 20% of revision knees showed evidence of aseptic lucency progression in one or more zones. No radiographic evidence of aseptic loosening was noted in this review. Documented sepsis occurred in one primary knee and two revision knees. Patellar instability occurred in 21% of primary knees and 36% of revision knees, representing the major complication. The Kinematic Rotating Hinge prosthesis is intended for use in arthroplasty cases where there is functional absence of collateral ligament stability. This review suggests that a high percentage of satisfactory clinical results can be achieved with this prosthesis with long-term radiographic stability.     

Infection after an open supracondylar fracture above a total knee arthroplasty treated with the supracondylar nail

A 72-year-old man with an open fracture above a total knee arthroplasty was treated with a supracondylar intramedullary nail. Five months after internal fixation, the patient developed a Staphylococcus aureus infection of the knee, which resolved after a 42-day course of IV antibiotics. After reimplantation with a posteriorly stabilized condylar total knee arthroplasty using femoral and tibial stems with vancomycin-impregnated cement, the patient has been pain-free and ambulatory at 8 months' follow-up. The supracondylar nail may be an acceptable internal fixation device for closed fractures above a total knee arthroplasty, but, if possible, open fractures in this location may be better treated with fixation devices that do not violate the knee joint.     

Supracondylar fractures of the femur above total knee arthroplasties with cortical allograft struts

Ten supracondylar fractures of the femur above a total knee arthroplasty were treated with open reduction and internal fixation using a metal plate and cortical allograft struts. Failure with nonunion of previous operative treatments was seen in 5 patients. The other 5 patients had either severe osteopenia or comminution of the fracture above the knee prosthesis. At an average of 38 months' follow-up, all the fractures healed with an average union time of 17.6 weeks. The postoperative knee alignment averaged 5.1 degrees valgus. Infection occurred in 1 patient, which resulted in a poor outcome. The remaining 9 patients were functioning well at the most recent follow-up examination. The use of cortical allograft struts combined with a compression plate provided satisfactory results for supracondylar fractures above knee prostheses with severe osteopenia or loss of bone stock after initial failure of internal fixation.     

Results of revision total knee arthroplasties using condylar prostheses. A review of fifty knees

Revisions of total knee arthroplasties for aseptic failure have provided varied results. In this review of fifty revisions in which a condylar prosthesis was used in carefully selected knees, the results were rated good or excellent in 76 per cent after an average length of follow-up of 4.8 years. At the follow-up examination, radiolucent lines were seen in 17 per cent of the knees. The complications included loosening of one or both prosthetic components in three knees (of which two were revised again); a hematoma in one knee; and a piece of loose cement, which had to be removed, in one knee. There were no deep infections. On the basis of these results, we concluded that revision total knee arthroplasty using a condylar prosthesis will have infrequent complications and will provide a satisfactory result in properly selected patients.