Tibial plateau stress fracture after unicondylar knee arthroplasty using a navigation system: two case reports

Distal Femur Intraarticular Fracture in a Late Arthritic Knee Treated With Osteosynthesis and Computer Navigation Assisted Primary Total Knee Replacement: A Case Report

The incidence of osteoporosis and osteoarthritis is on the rise. What further complicates the scenario is a stress fracture in a weight-bearing joint such as a knee in the presence of arthritis, making the treatment challenging. Prolonged immobilization associated with osteosynthesis increases morbidity and mortality in elderly patients. Primary total knee arthroplasty (TKA) has been advocated as a treatment modality in patients with distal femoral fractures who already have painful arthritic knees. Most of these injuries get treated using a hinged prosthesis. However, there are concerns about the high rate of loosening and mechanical failure of this type of prosthesis. This report presents a distal femur intraarticular fracture nonunion in the late arthritic knee, which is a rare presentation as proximal tibia stress fractures are more common. This was treated with osteosynthesis, and computer navigation assisted primary total knee replacement using medial pivot knee in a 54-year-old male with a body mass index of 38. Based on clinical and radiographic evidence, primary total knee replacement and plate osteosynthesis are viable options for distal femur fractures with osteoarthritis using computer navigation. While limiting the number of procedures, it meets two prerequisites: early weight bearing, limiting decubitus-related complications, and early mobilization leading to patient autonomy.

Comparable incidence of periprosthetic tibial fractures in cementless and cemented unicompartmental knee arthroplasty: a systematic review and meta-analysis

PURPOSE

(I) To determine the incidence of periprosthetic tibial fractures in cemented and cementless unicompartmental knee arthroplasty (UKA) and (II) to summarize the existing evidence on characteristics and risk factors of periprosthetic fractures in UKA.

METHODS

Pubmed, Cochrane and Embase databases were comprehensively searched. Any clinical, laboratory or case report study describing information on proportion, characteristics or risk factors of periprosthetic tibial fractures in UKA was included. Proportion meta-analysis was performed to estimate the incidence of fractures only using data from clinical studies. Information on characteristics and risk factors was evaluated and summarized.

RESULTS

A total of 81 studies were considered to be eligible for inclusion. Based on 41 clinical studies, incidences of fractures were 1.24% (95%CI 0.64-2.41) for cementless and 1.58% (95%CI 1.06-2.36) for cemented UKAs (9451 UKAs). The majority of fractures in the current literature occurred during surgery or presented within 3 months postoperatively (91 of 127; 72%) and were non-traumatic (95 of 113; 84%). Six different fracture types were observed in 21 available radiographs. Laboratory studies revealed that an excessive interference fit (press fit), excessive tibial bone resection, a sagittal cut too deep posteriorly and low bone mineral density (BMD) reduce the force required for a periprosthetic tibial fracture to occur. Clinical studies showed that periprosthetic tibial fractures were associated with increased body mass index and postoperative alignment angles, advanced age, decreased BMD, female gender, and a very overhanging medial tibial condyle.

CONCLUSION

Comparable low incidences of periprosthetic tibial fractures in cementless and cemented UKA can be achieved. However, surgeons should be aware that an excessive interference fit in cementless UKAs in combination with an impaction technique may introduce an additional risk, and could therefore be less forgiving to surgical errors and patients who are at higher risk of periprosthetic tibial fractures.

LEVEL OF EVIDENCE

V.

Stress fracture of proximal tibia after proximal fibula osteotomy: A case report

Introduction

Proximal fibula osteotomy (PFO) is a new method for treating medial compartment osteoarthritis of the knee, which is based on the theory of differential settlement (nonuniform settlement). This procedure has been widely recognized for its advantages of relative simplicity, low rate of postoperative complications, and low postoperative costs. Stress fracture of the proximal tibia after PFO has not been previously reported.

Case presentation

We report a 62-year-old woman with chronic rheumatoid arthritis (RA) underwent left PFO for chronic knee pain, who developed a stress fracture of the proximal tibia more than 1 year after PFO.

Clinical discussion

In the early stage of proximal tibia stress fracture, due to the concealment of radiography manifestations, doctors from another hospital performed total knee arthroplasty (TKA) for the patient. They ignored the treatment of stress fracture of the proximal tibia, and the stress fracture was further aggravated after surgery. Six months later, the patient underwent open reduction and internal fixation with a plate and screw in the left proximal tibia fracture at our hospital. The patient was followed up at the hospital three months after open reduction, and the proximal tibia stress fracture began to heal.

Conclusion

RA is usually not confined to the medial compartment and its pathogenesis is different from that of osteoarthritis. Therefore, PFO is not an appropriate procedure for this type of patient.

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Stress fracture of proximal tibia after PFO has not been previously reported.

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This case is extremely rare of a stress fracture of the proximal tibia more than 1 year after PFO.

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RA is usually not confined to the medial compartment that PFO is not an appropriate procedure for this type of patient.

Medial Tibial Plateau Stress Fracture Following Navigated Total Knee Arthroplasty: Two Case Reports

Case series

Patients: Female, 47-year-old • Female, 58-year-old

Final Diagnosis: Periprosthetic fracture

Symptoms: Medial knee pain • varus deformity

Medication: —

Clinical Procedure: —

Specialty: Orthopedics and Traumatology

Dependence of knee range of motion on the alignment of femoral and tibial components after medial unicompartmental knee arthroplasty

INTRODUCTION

This study evaluated the relationship between postoperative knee flexion angles and the position of femoral and tibial components in unicompartmental knee arthroplasty (UKA).

MATERIALS AND METHODS

Eighteen patients (a total of 22 knees: three men, four knees; 15 females, 18 knees) who underwent navigation-assisted UKA were included. Pre- and postoperative computed tomography images were applied on 3D software, which were matched and used to calculate the position of femoral and tibial components. Correspondingly, we investigated the relationship between the knee range of motion (ROM) at 1-year postoperative follow-up and the position of femoral and tibial components.

RESULTS

At 1-year post-UKA, the knee flexion angle was associated with the posterior flexion angle of tibial components. This particular angle was significantly greater in the group with equal or greater postoperative knee ROM compared to preoperative ROM (5.2 ± 2.1°) than in the group with less postoperative knee ROM compared to preoperative ROM (2.6 ± 1.6°, p < 0.01). There was no significant difference between both groups in the femoral component position, preoperative posterior slope of the medial tibial plateau, change in the pre- to postoperative posterior tibial slope, and postoperative knee society score.

CONCLUSION

The posterior flexion angle of the tibial component affected the improvement/deterioration of the postsurgery knee flexion angle in navigation-assisted UKA. For improved outcomes after UKA using navigation systems, surgeons should aim to achieve a 5° to 8° posterior flexion angle of the tibial component.

Computer assisted orthopaedic surgery: Past, present and future

Computer technology is ubiquitous and relied upon in virtually all professional activities including neurosurgery, which is why it is surprising that it is not the case for orthopaedic surgery with fewer than 5% of surgeons using available computer technology in their procedures. In this review, we explore the evolution and background of Computer Assisted Orthopaedic Surgery (CAOS), delving into the basic principles behind the technology and the changes in the discussion on the subject throughout the years and the impact these discussions had on the field. We found evidence that industry had an important role in driving the discussion at least in knee arthroplasty-a leading field of CAOS-with the ratio between patents and publications increased from approximately 1:10 in 2004 to almost 1:3 in 2014. The adoption of CAOS is largely restrained by economics and ergonomics with sceptics challenging the accuracy and precision of navigation during the early years of CAOS moving to patient functional improvements and long term survivorship. Nevertheless, the future of CAOS remains positive with the prospect of new technologies such as improvements in image-guided surgery, enhanced navigation systems, robotics and artificial intelligence.

Tibial plateau fracture related to unicompartmental knee arthroplasty: Two case reports and literature review

RATIONALE

Unicompartmental knee arthroplasty (UKA) is an effective method to treat single compartment disease of the knee joint. Report about the complications of UKA, especially tibial plateau fractures, is rare. Given its rarity, its pathogenesis is not well described, and a standard of treatment is still not established. Therefore, relevant studies and analysis of this complication have a significant effect on helping physicians avoid risks and guide clinical diagnosis and treatment.

PATIENT CONCERNS

The 1st case corresponds to a 70-year-old male patient who complained of knee pain, difficulty walking, nocturnal rest pain, and elevated skin temperature at 3 weeks after the left knee arthroplasty. The second case is a 72-year-old female patient who complained of left knee pain and swelling during movement at 2 weeks after the left knee arthroplasty.

DIAGNOSIS

The 1st case showed a fracture of the medial malleolus of the left knee and a secondary depression of the medial tibial plateau in X-rays and the second case showed a fracture of the medial malleolus of the left knee in computed tomography (CT) and X-rays.

INTERVENTIONS

The 1st case was treated with plate and screw fixation and the second case was treated conservatively and immobilized using brace and remained nonweight bearing for 6 weeks.

OUTCOMES

After 1 year, both patients have good joint activity, and there was no pain or loosening of the prosthesis and fragment displacement.

LESSONS

The incidence of tibial plateau fractures (TPF) related to UKA might be low, but fatal and difficult to treat. Its pathogenesis determines procedure-related factors; when fracture develops, treatment should be based on the degree of displacement, stability of implant fixation, etc.

Proximal tibia stress fracture with Osteoarthritis of knee - Radiological and functional analysis of one stage TKA with long stem

INTRODUCTION

Proximal tibia stress fractures with knee osteoarthritis pose a challenging situation. We evaluated the radiological and functional outcome of one-stage total knee arthroplasty (TKA) and long stem for patients with varied grades of knee arthritis and proximal tibia stress fractures.  Methods: We analysed 20 patients from April 2012 to March 2017 with proximal tibia stress fractures associated with knee osteoarthritis of varied grades. Out of 20 patients, five were acute fresh fractures. The mean age was 64 years (range, 52-78) which includes three men and 17 women. Previous surgery in the same limb, rheumatoid arthritis, valgus deformity were excluded. All patients were treated with posterior stabilised TKA with long stem, of which, four patients had screw augmentation for medial tibial bone defect and two patients with malunited fracture at stress fracture site required osteotomy, plating and bone grafting. Two patients had two level stress fracture of tibia in the same leg.

RESULTS

The mean follow-up period was 28 (range, 6-60) months. The mean tibiofemoral angle improved from 18.27° varus to 1.8° valgus. The mean knee society score improved from 21.9 (range, -10 to 45) to 82.8 (range, 15-99) [p < 0.05]. The mean Knee Society functional score improved from 15.5 (range, -10 to 40) to 76.8 (range, 10-100) [p < 0.05]. All fractures got united at the last follow-up. One patient had infection and wound dehiscence at six months for which debridement done and had poor functional outcome.

CONCLUSION

TKA with long stem gives excellent outcome, irrespective of severity of arthritis associated with stress fracture. By restoring limb alignment and bypassing the fracture site, it facilitates fracture healing. Early detection and prompt intervention is necessary to prevent the progression to recalcitrant non-union or malunion.

Stress fracture of the proximal fibula after total knee arthroplasty

We report a rare case of proximal fibular fatigue fracture developing 14 years after total knee arthroplasty in a known case of rheumatoid arthritis. A valgus deformity of the knee can put abnormal stress on the upper fibula leading to its failure. We believe that, as the fibula acts as an important lateral strut, its disruption due to a fracture led to rapid progress of the valgus deformity of the knee in this patient.

Bilateral periprosthetic tibial stress fracture after total knee arthroplasty: A case report

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Periprosthetic tibia fractures are rare cases.

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Bilateral tibial stress fracture developed after total knee arthroplasty is the first of its kind in the literature.

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A stress fracture should be kept in mind in the persistent pain in the upper end of the tibia that occurs after surgery.

Introduction

Periprosthetic fractures around the knee after total knee arthroplasty can be seen in the femur, tibia and patella. The tibial fractures are rare cases. Our case with bilateral tibial stress fracture developed after total knee arthroplasty (TKA) is the first of its kind in the literature.

Presentation of case

75-year-old male patient with bilateral knee osteoarthritis had not benefited from conservative treatment methods previously applied. Left TKA was applied. In the second month postoperatively, periprosthetic tibial fracture was identified and osteosynthesis was implemented with locked tibia proximal plate-screw. Bone union in 12 weeks was observed in his follow-ups.

After 15 months of his first operation, TKA was applied to the right knee. Postoperatively in the second month, as in the first operation, periprosthetic tibial fracture was detected. Osteosynthesis with locking plate-screw was applied and union in 12 weeks was observed in his follow-up.

He was seen mobilized independently and without support in the last control of the case made in the 24th month after the second operation.

Discussion

The number of TKA applications is expected to increase in the future. The incidence of periprosthetic fractures should also be expected to increase in these cases. Periprosthetic tibial fractures after TKA are rarely seen. The treatment of periprosthetic fractures around the knee after TKA can be difficult.

Conclusion

In the case of persistent pain in the upper end of the tibia after the surgery, stress fracture should be considered.

One-stage long-stem total knee arthroplasty for arthritic knees with stress fractures

PURPOSE. To evaluate the outcome of one-stage long-stem total knee arthroplasty (TKA) for patients with arthritic knees and tibiofemoral stress fractures. METHODS. Records of 11 men and 18 women aged 47 to 78 (mean, 66) years who underwent fixed-bearing posterior-stabilised TKA for osteoarthritis or rheumatoid arthritis of the knee with tibial (n=31) and femoral (n=3) stress fractures were reviewed. All the tibial fractures involved the proximal half. There were 7 associated fibular stress fractures. Of the 31 knees with tibial stress fractures, 26 and 5 manifested varus and valgus deformity, respectively. RESULTS. The mean follow-up period was 51 (range, 24-96) months. The mean tibiofemoral angle improved from 23.2 to 1.9 degrees varus. The mean Knee Society knee score improved from 38.5 (range, 15- 63) to 89.6 (range, 80-95) [p<0.05]. The mean Knee Society functional score improved from 25.5 (range, 0-40) to 86.5 (range, 60-100) [p<0.05]. All fractures were united at the last follow-up. No complications were encountered. CONCLUSION. One-stage long-stem TKA restores limb alignment and facilitates fracture healing, with excellent outcome.

Comparison of high tibial osteotomy and unicompartmental knee arthroplasty at a minimum follow-up of 3 years

The purpose of this study was to compare clinical outcomes including return to recreational activities (cycling, swimming, exercise walking, dancing, jogging, and mountain climbing) after opening-wedge high tibial osteotomy (HTO) and unicompartmental knee arthroplasty (UKA). Clinical outcomes were assessed using Tegner activity scores, ranges of motion, and Lysholm knee scores. In both groups, the number of patients participating in recreational activities was significantly reduced after surgery, but without a significant intergroup difference (1.3 activities in HTO group and in 1.6 activities in UKA group). Average Tegner activity scale scores, ranges of motion, and Lysholm knee scores did not show significant differences between the 2 groups. This study identified no significant differences between HTO and UKA for medial unicompartmental osteoarthritis in terms of return to recreational activity and short-term clinical outcomes.

Computer-assisted total knee arthroplasty is currently of no proven clinical benefit: a systematic review

BACKGROUND

Navigated total knee arthroplasty (TKA) may improve coronal alignment outliers; however, it is unclear whether navigated TKA improves the long-term clinical results of TKA.

QUESTIONS/PURPOSES

Does the literature contain evidence of better long-term function and lower revision rates with navigated TKA compared with conventional TKA?

METHODS

A systematic literature review was conducted of navigated TKA reviewing articles related to coronal alignment, clinical knee and function scores, cost, patient satisfaction, component rotation, anteroposterior and mediolateral stability, complications, and longer-term reports.

RESULTS

Coronal plane alignment is improved with navigated TKA with fewer radiographic outliers. We found limited evidence of improvements in any other variable, and function was not improved. The duration of surgery is increased and there are unique complications related to navigated TKA. The long-term benefits of additional increase in accuracy of alignment are not supported by any current evidence.

CONCLUSIONS

The findings in reports of navigated TKA should be interpreted with caution. There are few short- and medium- and no long-term studies demonstrating improved clinical outcomes using navigated TKA. Despite substantial research, contradictory findings coupled with reservations about the cost and efficacy of the technology have contributed to the failure of computer navigation to become the accepted standard in TKA. Longer-term studies demonstrating improved function, lower revision rates, and acceptable costs are required before navigated TKA may be widely adopted. In the future, with improvements in study design, methodology, imaging, navigation technology, newer functional outcome tools, and longer-term followup studies, we suspect that navigated TKA may demonstrate yet unrecognized benefits.

Navigation in minimally invasive unicompartmental knee arthroplasty has no advantage in comparison to a conventional minimally invasive implantation

INTRODUCTION

Minimally invasive implantation of unicompartmental knee prostheses can shorten rehabilitation time and lead to better functional results than conventional implantation. Exact positioning of the implant should be achieved, as this is a factor for the long-term survival of the prosthesis, although malpositioning can result due to the poor intraoperative view when using the minimally invasive approach. Navigation of the unicompartmental prosthesis could lead to a better implant positioning without losing the advantages of a minimally invasive approach.

MATERIALS AND METHODS

The same unicondylar knee prosthesis was implanted in a total of 40 patients, of whom 20 were implanted using navigation (kinematic navigation) and 20 using a conventional technique. The operating time was assessed in both groups. The orientation of the tibial and femoral implants was assessed radiologically postoperatively. We analysed these results according to the optimal positioning range proposed by the manufacturer. Furthermore, we examined the clinical results with the knee society score (KSS).

RESULTS

A good positioning of the prosthesis was observed in both techniques with only 11% of the radiologic measurements out of the proposed optimal range in each group. The operating time was significantly longer in the navigation group (17 min). The KSS did not differ between both groups at a follow-up of 16 resp. 18 months (navigated group: 184 points, conventional group: 178 points).

CONCLUSIONS

Navigation did not lead to a better positioning of the prosthesis than the conventional method and the operating time was longer. The clinical results were similar in both groups. The navigation may be a useful help for surgeons performing less unicompartmental knee arthroplasty using a minimally invasive approach.

Tibial shaft stress fractures resulting from placement of navigation tracker pins

The use of navigation during joint arthroplasty is believed to allow better placement of components. Gross fracture or stress fracture through navigation tracker pin placement is a complication reported in the literature. This case series presents details of stress fracture of tibial shaft through navigation pin track in 3 patients of 220 cases who underwent total knee arthroplasty at our institution. All the fractures eventually healed after a course of protected weight bearing. As a result, we use smaller-diameter self-tapping and self-drilling pins routinely and avoid placement of pins in the diaphysis and ensure that pins are inserted in different plains during insertion into metaphysis.

Pin track induced fractures around computer-assisted TKA

BACKGROUND

Navigation tracker pins rigidly fixed to bone is a prerequisite for computer-assisted total knee arthroplasty. The first cases of fracture on navigation tracker pin sites have recently been reported.

HYPOTHESIS

The risk of fracture depends first on diaphyseal placement of the tracker pins, and second on "transcortical" tangential route of the tracker pin as well as failure to obtain rigid fixation.

MATERIAL AND METHODS

In a continuous series of 385 total knee arthroplasties, five patients (four women, one man) on average 73.2 years old (range: 65-79 years old) have sustained femoral fractures at the tracker pin site (incidence 1.3%). We investigated the demographic and radiological factors contributing to this complication.

RESULTS

The patients with fractures were obese or overweight with an average body mass index of 32.56 (range: 25.14-39.45) but this was not statistically different from the BMI of the population of patients without fractures. The average delay from arthroplasty to fracture was 12.6 weeks (range 7-21). The fracture was always preceded by several days of thigh pain and occurred after a minor trauma. The fractures were always simple originating from the tracker pin site. In four out of five cases, the tracker pins were placed in the diaphyseal femur, and in all cases at least one pin was transcortical. Closed endomedullary nailing or ORIF were performed in five cases, with no bone graft. Union was obtained with functional results that were equivalent to those before the fracture.

DISCUSSION

Fractures at the navigation tracker pin site are a complication which must be understood and explained to patients undergoing computer-assisted TKA because of the 1.3% incidence described in our series. The circumstances systematically associated with this type of fracture were: occurrence a certain amount of time after arthroplasty in obese patients who had pain before the fracture occurred. These fractures are favored by suboptimal placement of the tracker pins, especially in the lower diaphysis of the femur and transcortical fixation of at least one of the pins. Treatment included stable osteosynthesis and did not affect the results of total knee arthroplasty. The development of thigh pain some time after surgery in high risk patients (obesity, tracker pin site in the lower diaphysis, transcortical fixation) should suggest this diagnosis and weight-bearing should be avoided because these fractures are assimilated with stress fractures. Bicortical metaphyseal fixation should be the preferred tracker pin positioning for navigated total knee arthroplasty.

LEVEL OF EVIDENCE

Level IV retrospective study.

Evaluation of patients with a painful total knee replacement

Evaluation of patients with painful total knee replacement requires a thorough clinical examination and relevant investigations in order to reach a diagnosis. Awareness of the common and uncommon problems leading to painful total knee replacement is useful in the diagnostic approach. This review article aims to act as a guide to the evaluation of patients with painful total knee replacement.