Well-fixed Total Knee Research Articles

Circular hexapod external fixation for periprosthetic tibial fracture.

A poor soft tissue envelope often accompanies periprosthetic tibia fracture around a well-fixed total knee arthroplasty and the tibial stem leaves little room for screw fixation. This article describes the practicability and effectiveness of a novel surgical technique using circular hexapod external fixation, in patients with this clinical scenario. It was applied for fixation of periprosthetic tibia fracture in 2 patients. Contact between the external fixation pins and the prosthesis was avoided. Using a web-based software program, a gradual reduction in all planes was achieved. Adequate fixation, stability, reduction, and quick healing were obtained in the 2 cases, with minimal complications. The patients returned to their activity level a few months after external fixation removal.

Intramedullary Nailing of Tibial Shaft Fractures Distal to Total Knee Arthroplasty

Tibial shaft fractures distal to total knee arthroplasty are rare, but they are likely to become more common with the increasing number of arthroplasty procedures being performed. These fracture patterns have been treated in the past either with closed reduction and casting/bracing or with open reduction internal fixation using plates. Weight-bearing precautions in the elderly patient population can affect patient disposition, and weight bearing on extramedullary fixation can lead to early hardware failure. We present a series of nailing techniques that can be used for tibial fractures distal to a well-fixed total knee arthroplasty that avoids the tibial baseplate, provides stable fracture fixation, and allows for early weight bearing.

Getting out the well-fixed knee: All hands on deck

A well-fixed total knee arthroplasty can be removed using a systematic, stepwise approach. After establishing a preoperative diagnosis and ensuring that appropriate extraction instrumentation is available, the components of a successful explantation include appropriate superficial and deep exposure, protection of the extensor mechanism, a mobile surgical window, and careful, thorough disruption of the bone–implant or cement–implant interface. To facilitate explantation, the tibial insert, femoral implants, and tibial implants should be removed in sequence while minimizing forceful extraction to preserve bone stock. Keys to a successful reconstruction include augmenting or restoring bone loss, maintaining the joint line, balancing flexion and extension gaps, maintaining appropriate femoral rotation, and utilizing the appropriate level of implant constraint.

Prophylactic Free Flap for Chronic Lower-Extremity Soft-Tissue Defect Prior to Total Knee Arthroplasty: A Case Report.

Attempting total knee arthroplasty in patients with preoperative periarticular soft-tissue defects can result in disastrous postoperative complications. Orthopaedic surgeons often fail to appropriately evaluate and plan the management of these skin defects, which can lead to skin sloughing, necrosis, exposed total knee arthroplasty hardware, and the need for additional intervention. As expected, the results from salvage soft-tissue protocols are mixed1-9. Salvage soft-tissue procedures are undertaken in the setting of well-fixed total knee arthroplasty hardware and a compromised soft-tissue envelope rather than in the preoperative state. Infection risk is substantially higher once hardware has been placed, and the results are often poor with regard to functional rehabilitation and recovery10,11. Because of less than optimal results, some surgeons have attempted to prophylactically treat such soft-tissue defects. Expanders have been used to stretch tissue to increase soft-tissue coverage prior to total knee arthroplasty, but this approach has an increased risk of infection12,13. Simultaneous flap coverage in the setting of total knee arthroplasty has also been reported with good results14. Additionally, there are a few reports on prophylactic soft-tissue coverage in a staged fashion several months prior to total knee arthroplasty10,11. These studies discuss many benefits from treating the soft-tissue deficit prior to implantation. The local soft-tissue environment dictates the choice of coverage. The gold standard for coverage about the knee is the gastrocnemius rotational flap, which has excellent results, especially in a setting of infection1-4,7,15. Free flaps are considered in situations where local tissue is inadequate13,16. Free-flap options for the lower extremity include the rectus abdominis muscle, latissimus dorsi muscle, anterolateral thigh, and deep inferior epigastric perforator (DIEP), among others. We present a …

What Do You Do with the Unstable, Well-Fixed Total Knee Arthroplasty?

What Do You Do with the Unstable, Well-Fixed Total Knee Arthroplasty?

The Use of a Revision Femoral Stem to Manage a Distal Femoral Periprosthetic Fracture in a Well-Fixed Total Knee Arthroplasty

Managing very distal femoral periprosthetic fracture above a total knee arthroplasty (TKA) is a difficult problem. When a cruciate sacrificing TKA is used, bone stock around the implant is compromised and, therefore, can limit fixation options. We present technique using the revision system femoral stem for the PFC Sigma TKA (Depuy; Leeds, England) to stabilize this particular type of fracture.

Removal of the Well-Fixed Total Knee

This paper describes techniques for the removal of well-fixed cemented or cementless total knee implants. The principles of exposure, bone stock preservation, and control of the removal process are critical to the success of this procedure.

Locking Compression Plates for the Treatment of Periprosthetic Femoral Fractures Around Well-Fixed Total Hip and Knee Implants

There are currently few published studies examining the use of locking compression plates for the treatment of periprosthetic femoral fractures. Fifteen total hip or knee arthroplasty patients with 16 Vancouver type B1 and C fractures with an average age of 76 years were fixed and followed clinically and radiographically for 2 years. Fourteen patients achieved radiographic union by 6 months, and 13 patients were ambulatory by 6 months. There were no intraoperative complications. In summary, locking plates offer a viable treatment option for these difficult fractures. We advocate a minimum of 10 cortices of fixation (with unicortical or bicortical screws and cable combinations) above and below the fracture. Bone grafting should be used if the soft tissue envelope is violated with extensive dissection, and cortical struts should be considered in cases of failed hardware and revision fixation.

Fixation of Periprosthetic Femur Fractures Above Total Knee Arthroplasty With the Less Invasive Stabilization System: A Midterm Follow-Up Study

The complication rate of periprosthetic femoral fractures above well-fixed total knee arthroplasties is high. The Less Invasive Stabilization System (LISS) was introduced to reduce surgical dissections at the fracture site. The purpose of this retrospective study was to evaluate the midterm functional outcome of a group of patients with periprosthetic fractures above well-fixed total knee arthroplasties treated with the LISS. Between January 1999 and June 2004, 23 consecutive patients (all women) with periprosthetic fractures above well-fixed total knee arthroplasties were treated with the LISS. The mean age was 77 years (range, 61-90 years). Nineteen of the patients (83%) were seen after a midterm follow-up of 46 months (range, 26-67 months). Three patients (13%) died, and one patient (4%) was lost to follow-up. A proximal screw pull-out of the internal fixator occurred in one patient (4%). All fractures healed within a mean of 14 weeks (range, 9-21 weeks). No bone graft was required. There were two delayed unions, no nonunions or infections. One patient (4%) had a malalignment with 7° varus. The mean range of motion was 102° (range, 65-120°). The mean knee score of the Knee Society was 81 points (range, 65-90 points), and the mean function score of the Knee Society was 56 points (range, 35-90 points). We found that a minimally invasive, locked plating system permitted stable fixation, early knee motion with good midterm results, and minimal complications. These techniques should be used in place of less stable and more invasive methods.

High-dose antibiotic infusion for infected knee prosthesis without implant removal

BackgroundRetention of a prosthesis represents an attractive surgical modality for the infected but well-fixed knee prosthesis because patients need to stay in bed after removal of all components. Some additional postoperative treatment would be needed, however, when treated only with débridement because of its low success rate. MethodsIn this study, intraarticular antibiotic infusion into the infected joints after débridement, while retaining the implants, was performed for six well-fixed total knee arthroplasties (TKAs), one revision TKA, and five tumor megaprostheses with an average follow-up period of 47.5 months (range 20–82 months). TKA patients with a polyethylene insert or those with all exchangeable components and all polyethylene parts in tumor megaprostheses underwent device removal and thorough débridement of the soft tissues. Subsequently, new polyethylene inserts were implanted in the TKA patients. The removed metallic prostheses were resterilized and reimplanted, and new polyethylene inserts were implanted in the tumor megaprostheses patients. The wound was closed in layers after insertion of a catheter percutaneously. The patients received organism-specific intraarticular antibiotics through the catheter twice a day until the infection disappeared clinically. ResultsThere was no recurrence of infection in the TKA and revision TKA patients. Four of five knees treated with tumor megaprostheses exhibited recurrence of the infection. Infection was finally healed, however, in all cases by the same treatment procedure. ConclusionsAlthough some patients experienced recurrence of infection, successful implant salvage was achieved in all cases with the same treatment procedure. Patients do not need to stay in bed during this treatment. Therefore, this method should be considered as one of the treatment options for infected knee prostheses.

Granuloma debridement and the use of an injectable calcium phosphate bone cement in the treatment of osteolysis in an uncemented total knee replacement

Polyethylene particulate debris-induced periprosthetic osteolysis is a known complication of knee arthroplasty surgery, and may result in the need for revision surgery. The management of these bony defects can be surgically challenging, and full revisions of well-fixed total knee components can lead to substantial bone loss. We present the case of a 71 year old man who developed knee pain and osteolysis around an uncemented total knee replacement. Due to significant medical comorbidies he was treated by percutaneous cyst granuloma debridement and grafting using an injectable calcium phosphate bone substitute. There were no wound complications, and the patient was allowed to fully weight-bear post-operatively. Histopathology and microbiology of the cyst material confirmed polyethylene granulomata without any evidence of infection. At 6 weeks post-operatively the patient's previous knee pain had resolved, he was able to comfortably fully weight-bear. Preoperative scores (Knee Society Score (KSS) 41, WOMAC score 46.2, and Oxford Knee Score 39) had all improved at the 12-month post-operative review KSS 76, WOMAC 81.7 and Oxford Knee score 21). This is a safe and effective technique with minimal morbidity and may be an appropriate treatment modality when more extensive revision surgery is not possible. The case is discussed with reference to the literature.

Periprosthetic Femoral Fracture After a Well-Fixed Revision Total Knee Arthroplasty Treated With In Situ Effective Lengthening of Prosthesis

The increasing number of total knee arthroplasties implies a greater likelihood of periprosthetic fractures and need for successful treatment options. We report a case where in situ effective lengthening of the stem of a well-fixed indwelling prosthesis by a custom-made intramedullary nail with taper-lock coupling provided a successful alternative to the established internal fixation techniques involving prosthesis exchange. We believe that effective lengthening of indwelling prosthesis by a custom-made intramedullary nail is an effective option for treating periprosthetic femoral fractures in selected cases, where an attempt of removing well-fixed implant would result in unacceptable bone loss at the joint level.

Operative treatment of distal femoral fractures above total knee arthroplasty with the indirect reduction technique: A long-term follow-up study

The complication rate of conventional plate osteosynthesis (CPO) of periprosthetic femoral fractures above total knee arthroplasties (TKA) is high. Indirect reduction techniques were introduced to reduce surgical dissection at the fracture site. Twenty-one patients (4 men and 17 women) with femoral fractures above well-fixed total knee arthroplasties were consecutively treated with the indirect reduction technique. AO/ASIF (Arbeitsgemeinschaft für Osteosynthesefragen/Association for the Study of the Problems of Internal Fixation) Type 33A fractures were included. The mean age was 78 years (range, 67–94 years). Four fractures were stabilised with bone grafts, three in combination with bone cement. Nineteen of the patients were seen at a 1-year follow-up, 15 were seen after a long-term follow-up of 9 years (range, 7–12 years). There was only one implant failure in a comminuted fracture with severe osteoporosis, no infection, and no non-union. At the 1-year follow-up malalignment of 5° varus occurred in one patient. The mean range of motion of the eighteen patients was 98° (range, 65–110°). The mean knee society score was 74 (range, 62–84), the mean function score was 52 (range, 39–72). At the long-term follow-up, the mean range of motion of the patients was 101° (range, 65–115°). The mean knee society score was 77 (range, 65–88), the mean function score was 55 (range, 40–75). Our results suggest the 95° condylar blade plate in the indirect reduction technique is still a good implant with good long-term results. It works best in proximal fractures when there is minimal comminution of the distal fragment in the hands of an experienced trauma surgeon. Knee function and range of motion increased less over time.

Supracondylar nailing of periprosthetic fractures above total knee arthroplasties

Supracondylar nailing was performed in 10 patients who sustained periprosthetic fractures above total knee arthroplasties. The fractures occurred in women with an average age of 67.4 years (range, 42–92 years). All fractures healed in a satisfactory alignment in an average duration of 13.2 weeks (range, 12–18 weeks). None of the fractures needed bone grafting. There were no cases of wound infections, nonunion or delayed union. All patients achieved satisfactory range of movement of the knee joint and preoperative functional status. Main complications included loosening of a distal screw in one patient and fracture above the short nail following a second injury in another patient. Use of a longer nail where possible and a condylar bolt for distal locking can easily avoid these complications. We conclude that supracondylar nailing, despite some limitations, is a satisfactory method of treatment for a majority of displaced periprosthetic fractures above well-fixed total knee arthroplasties.

Modular Insert Exchange in Knee Arthroplasty for Treatment of Wear and Osteolysis

Wear and osteolysis have been successfully treated by modular polyethylene exchange in revision hip arthroplasty. However, studies of the same approach in revision knee arthroplasty have not provided similar results. We evaluated the results of isolated polyethylene exchange for wear and/or osteolysis in 68 press-fit condylar TKAs from four centers. At a minimum of 24 months after polyethylene exchange surgery (average, 44 months; range, 24-83 months), there were 11 failures (16.2%). Failures included aseptic loosening in 10 knees and infection in one. With the relatively small cohort size we were unable to identify factors that predicted which knees were more likely to fail: we observed no correlation between failure and patient demographics, component design, or use of cement versus bone graft augmentation. Radiographic review demonstrated no progression of osteolytic lesions in 97% of knees in the study. While the short-term followup limits the conclusions, we believe the 84% success rate with modular polyethylene exchange for wear and osteolysis and the lack of progression of osteolytic lesions in the majority of the knees are encouraging. Full revision of well-fixed total knee components can lead to substantial bone loss, particularly in the face of osteolysis and we therefore consider modular polyethylene exchange in press-fit condylar knees a reasonable option for wear and osteolysis. Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence

Management of periprosthetic femur fractures with a first generation locking plate

Periprosthetic femoral fractures associated with well-fixed total hip or total knee prostheses present a challenging management problem as these injuries typically occur in osteoporotic bone. Conventional management entails extensive periosteal stripping to allow for plate fixation. We reviewed a consecutive series of patients who sustained fractures associated with a well fixed total knee prosthesis, a total hip prosthesis, or both. Twenty four patients with a mean age of 69.4 years were included. All patients underwent fixation via percutaneous insertion techniques with a first generation locking plate and screws (LISS--Less Invasive Skeletal Stabilization, Synthes, Paoli, PA). Three patients sustained fractures distal to a well-fixed total hip prosthesis, eighteen fractures occurred above a well-fixed total knee femoral component, and three were interprosthetic. The mean length of time from the index procedure to fracture was 76 months, range (2-172 months). Blood loss was minimal in each case, with a mean operative time of 90 min (range 60-120 min). Twenty one of twenty four went on to unite at a mean 6.2 months (range 3-19 months). Three patients underwent further surgery. One failure of fixation was encountered. Percutaneous fixation is technically demanding as it requires stable fixation without direct visualisation of the fracture site or the entire fixation device. Our results suggest percutaneous fixation with the LISS plate is an effective although technically demanding method of treatment. Complication rates were comparable to existing reports of this treatment method, and appear to be improved over traditional methods of fixation.

Acute Sciatic Nerve Palsy Caused by a Polyethylene Granuloma Arising From a Well-fixed Total Knee Arthroplasty

We report the presentation of an acute sciatic nerve palsy, arising as a result of an inflammatory mass in the posterior thigh containing polyethylene debris from an adjacent, well-fixed total knee arthroplasty.

Removing Well-fixed Total Knee Arthroplasty Implants

Revision total knee arthroplasty requires the removal of one or all of the prior knee components. Thoughtful and careful removal of well-fixed total knee components can preserve host bone stock and facilitate subsequent reconstructive efforts. The tools and techniques for knee component removal include simple osteotomes, saws, extraction devices, ultrasonic devices, and frequently a combination of some or all of the above. It is the unique nature of each revision arthroplasty, which presents the surgeon with such challenge. Each of the techniques discussed in this review reflects the anecdotal experience acquired in over 800 revision total knee arthroplasties performed at our center. We review our empiric bias regarding the individual applicability of these techniques. Therapeutic studies, Level V (expert opinion). See Guidelines for Authors for a complete description of Levels of Evidence.

Use of a supracondylar nail for treatment of a supracondylar fracture of the femur following total knee arthroplasty

Treatment of displaced or comminuted supracondylar fractures of the femur following total knee arthroplasty is challenging and problematic. Closed treatment has been associated with malunion, nonunion, and loss of motion, whereas early operative treatment has been associated with infection as well as nonunion. Intramedullary fixation of these fractures has the theoretical advantage of preserving periosteal blood supply while allowing early motion. The use of a nail specifically designed for supracondylar femur fractures to treat a a periprosthetic fracture about a well-fixed total knee arthroplasty is reported. This device provides a valuable treatment option to the surgeon treating this difficult problem.

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.