Periprosthetic knee fractures. A review of epidemiology, risk factors, diagnosis, management and outcome

Management, outcome, and novel classification system of periprosthetic fractures in patients with transcutaneous osseointegrated prosthetic systems (TOPS)-a retrospective cohort analysis

INTRODUCTION

Transcutaneous osseointegrated prosthetic systems (TOPS) are anchored prosthetic systems for major limb loss. Sometimes TOPS patients suffer from periprosthetic fractures. The aim of this study was to analyze the management and outcomes of periprosthetic fractures in patients with TOPS and to introduce a novel classification system for this entity.

MATERIAL/METHODS

Since 2010, 140 patients were treated with TOPS after transfemoral amputation in two centers in Germany. Fifteen patients sustained periprosthetic fractures, with five intra- and ten postoperative fractures. The outcome was analyzed by Prosthesis Mobility Questionnaire (PMQ), K-level and prosthesis wear time per day. A subgroup analysis for the body mass index (BMI) was performed.

RESULTS

All postoperative fractures were treated with implant-retaining osteosynthesis. Fourteen fractures healed without complications after a mean of 3 months. One postoperative fracture developed a clinically asymptomatic firm non-union. No Endo-Fixstem had to be removed. For the fracture and control group, a significant increase of the PMQ (p < 0.001) and K-level (p < 0.001) was observed after TOPS treatment compared to the preoperative baseline. Furthermore, the subgroup analysis showed a significant increase of the PMQ and K-level for both normal weight (p = 0.002) and overweight patients (p < 0.001). Of interest, overweight patients even showed a significantly higher increase in scores compared to normal weight patients, regardless of periprosthetic fracture.

CONCLUSION

Periprosthetic fractures do not necessarily worsen outcomes of TOPS treatment. Proper classification and standardized appropriate treatment strategies according to fracture morphology are paramount for reliably good outcomes. We recommend to not remove or exchange the implant (Endo-Fixstem) even if it is assembly. Higher BMI did not have an impact onto rehabilitation success after TOPS to major limb loss of the lower extremity.

Risk factors of early periprosthetic femoral fracture after total knee arthroplasty

Background

Periprosthetic femoral fracture (PFF) is a serious complication after total knee arthroplasty (TKA). However, the risk factors of PFF in the early postoperative setting are not well documented. This study determines the risk factors of early PFF after primary TKA.

Methods

This study recruited 24 patients who had early PFF within postoperative 3 months and 96 control patients. Demographic data (age, gender, weight, height, body mass index, Deyo-Charlson comorbidity index, diagnosis, operated side, underlying diseases and history of steroid usage intraoperative outcomes), intraoperative outcomes (operative time, surgical approach, type and brand of the prosthesis), and radiographic outcomes (distal femoral width; DFW, prosthesis-distal femoral width ratio; PDFW ratio, anatomical lateral distal femoral angle; LDFA, the change of LDFA, femoral component flexion angle; FCFA and anterior femoral notching; AFN) were recorded and compared between groups. Details of PFF, including fracture pattern, preoperative deformity, and time to PFF were also documented.

Results

In univariate analysis, the PFF group had significantly older, right side injury, rheumatoid, dyslipidemia, Parkinson patients than the control group (p < 0.05). No cruciate-retaining design was used in PFF group (p = 0.004). Differences between the prosthetic brand used were found in this study (p = 0.049). For radiographic outcomes, PFF group had significantly lower DFW but higher PDFW ratio and postoperative LDFA than the control group (p < 0.05). While the change of LDFA, FCFA and AFN were similar between groups. The fracture patterns were medial condylar (45.8%), lateral condylar (25.0%) and supracondylar fracture (29.2%). The mean overall time to PFF was 37.2 ± 20.6 days (range 8–87 days). Preoperative deformity was significantly different among the three patterns (p < 0.05). When performed multivariate analysis using the logistic regression model, age was only an independent risk factor for early PFF. The cut-off point of age was > = 75 years, with a sensitivity of 75.0% and specificity of 78.1%.

Conclusion

This study determined that age was the independent risk factors for early PFF. However, further well-controlled studies with a larger sample size were needed to address this issue.

Mid-term clinical outcomes and complications of primary total knee arthroplasty in hemodialysis patients: a retrospective comparative cohort study

Background

Numerous patients who receive hemodialysis (HD) undergo total knee arthroplasty (TKA) due to advanced knee joint arthritis. However, there are few studies that describe the clinical outcomes and complications of TKA in HD patients. This study investigated the mid-term results of TKA in patients undergoing HD.

Methods

This single-center retrospective study compared clinical and surgical outcomes following TKA in patients who were receiving HD with those who were not. We used propensity scores to match 21 knees of 18 patients who received HD to 706 knees of 569 patients who had not received HD, from a total of 727 knees (587 patients) that underwent primary unilateral TKA. The clinical outcomes were evaluated using the American Knee Society Score-knee (AKSS-knee) and AKSS-function scores. The primary surgical outcome measure was the number of knees with postoperative complications.

Results

In both the HD and non-HD groups, postoperative AKSS-knee and function scores significantly improved when compared to preoperative values. Postoperative AKSS-knee and function scores were not significantly different between the groups. The number of knees with postoperative complications was larger in the HD group than the non-HD group within the first postoperative month, 0–12 months, 12–24 months, 0–24 months, and two years after surgery. Additionally, in the HD group, more complications occurred in the first month than any subsequent month in the two years after surgery.

Conclusions

TKA improves AKSS-knee and function scores equivalently for HD patients and non-HD patients. However, HD patients develop more complications after TKA, especially within the first month. Therefore, surgeons who perform TKA for HD patients should obtain informed consent after explaining the possible complications, and HD patients should be carefully observed following TKA.

Shaft Fractures in Patients Requiring Primary or Revision Total Knee Arthroplasty Can Be Successfully Treated with Long-Stemmed Implants without Additional Fixation

The aim of this study was to evaluate the bone union, complication rate, clinical and functional outcomes of long-stemmed total knee arthroplasty (TKA) in patients with periprosthetic femoral or tibial shaft fractures and in patients with femoral or tibial shaft fractures with coexisting advanced knee osteoarthritis (OA). This retrospective study comprised 25 patients who underwent surgery due to tibial or femoral shaft fractures: (1) with coexisting severe knee OA or (2) with a periprosthetic fracture requiring implant exchange. In all cases, fracture stabilization was performed intramedullary with the use of long-stemmed implants without the use of additional fixation material (plates, screws, or cerclage). Bone union was achieved in 22/25 patients (88%). One patient required revision with additional plate stabilization due to non-union, and asymptomatic partial bone union was observed in two cases. The group with periprosthetic fractures demonstrated good clinical (mean 73.1 ± 13.3) and moderate functional (mean 59.2 ± 18.8) outcomes in the Knee Society Scoring system (KSS). In the group with shaft fracture and coexisting OA significantly higher clinical (excellent results, mean 84.1 ± 11; p = 0.03) and functional (good results, mean 76.2 ± 20.6; p = 0.04) results were noted. There were no statistically significant differences in terms of range of motion (ROM) or complication rate between these two groups. One-stage TKA with a long-stemmed implant without the use of additional fixation material is an effective method for the treatment of femoral or tibial shaft fractures in patients who require joint replacement. Despite being technically demanding, the approach yields bone union and moderate to excellent clinical and functional outcomes with a relatively low complication rate.

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

Bilateral Periprosthetic Knee Fracture with the Right Floating Total Knee and Left Periprosthetic Patella Fracture Management Strategy: A Case Report

Introduction:

Periprosthetic fractures (PPFs) in total knee replacement are an uncommon condition. The floating knee injury around total knee arthroplasty (TKA) is even rare and poses challenges in management. Incidence is increasing due to growing primary joint arthroplasties and revision procedures. We report a case of bilateral PPF with a floating total knee.

Case Report:

A 74-year-old female involved in a violent car accident sustained bilateral knee injuries, facial, and hand injury. In the emergency room, the initial resuscitation and trauma protocol stabilization were done and she was provisionally immobilized for her limb injuries. She presented with the right-sided floating total knee involving periprosthetic periarticular comminuted distal femur fracture and midshaft comminuted fracture tibia fibula. The patient also had left knee lower pole periprosthetic patellar fracture. The patient had a history of bilateral TKA around 2 years back. She underwent surgical management of the right floating total knee by stabilization of distal femur fracture and tibial shaft fracture fixation with locking plates. She underwent primary autologous bone grafting for both fracture sites. The left knee patellar fracture was managed conservatively in a brace. At 8 months follow-up, the patient was pain free and had consolidation of fractures. The patient walked without any walking aids. At 18 months, she had regained her pre-injury functional status.

Conclusion:

Each fracture in a floating total knee injury is unique and treatment should be decided based on individual analysis and the extent of soft-tissue injuries. An uncommon occurrence highlights the complex injury patterns involving PPF requiring individualized case specific management strategy.

Anterior femoral notching ≥ 3 mm is associated with increased risk for supracondylar periprosthetic femoral fracture after total knee arthroplasty: a systematic review and meta-analysis

PURPOSE

Anterior femoral notching (AFN) may be associated with a higher risk for supracondylar periprosthetic fracture (sPPF) after total knee arthroplasty (TKA), although studies have yielded inconclusive results. We aimed to systematically investigate and meta-analyze the best available evidence regarding the association between AFN and the risk of sPPF after TKA.

METHODS

A comprehensive search of PubMed, Scopus, Mendeley, Google Scholar and Cochrane databases was performed, from conception to February 29, 2020. Data were expressed as odds ratio (OR) with 95% confidence intervals (CI). I²-index was employed for heterogeneity. Newcastle-Ottawa scale was implemented for quality assessment of the included studies.

RESULTS

Nine studies fulfilled the eligibility criteria, including a total of 3264 patients subjected to TKA. Among them, there were 150 patients who sustained a sPPF. Overall, patients exposed to AFN (AFN group) demonstrated an increased risk for sPPF compared to those not exposed (control group) (OR 3.91, 95% CI 1.22-12.58, p = 0.02; I² 68.52%). Subgroup analysis based on AFN depth with a cut-off value of 3 mm further clarified this association. Patients with AFN ≥ 3mm were at higher risk for sPPF compared to patients with AFN < 3 mm and control group (OR 4.85, 95% CI 2.08-11.33, p = 0.00; I² 0.0%). On the contrary, fracture risk was not significant for patients with AFN < 3 mm compared to the control group (OR 5.0, 95% CI 0.44-56.82, p = 0.19; I² 42.99%).

CONCLUSION

Patients, exposed to AFN ≥ 3 mm in depth, are at higher risk for sustaining a sPPF.

Sister, Sister! Siblings With Simultaneous Early Femoral Insufficiency Fractures After Total Knee Arthroplasty

Early periprosthetic fractures after total knee arthroplasty are rare but devastating complications which require revision surgery and lead to poor patient satisfaction. We present 2 siblings who underwent primary total knee arthroplasty on the same day and then both presented 2 weeks after surgery with atraumatic periprosthetic femur fractures. The first patient underwent revision for a cemented distal femoral replacement with stemmed tibial fixation. The second patient underwent an isolated femoral component revision with a stemmed femoral component and distal augment. Histological evaluation identified significant peri-implant osteoporosis. The variation in complexity associated with early periprosthetic femoral insufficiency fractures is highlighted by these 2 cases. Surgeons may consider using stemmed femoral components in similar patients if poor distal femoral bone stock is encountered intraoperatively.

Biomechanics of Implant Fixation in Osteoporotic Bone

PURPOSE OF REVIEW

The purpose of this review is to critically evaluate the current literature regarding implant fixation in osteoporotic bone.

RECENT FINDINGS

Clinical studies have not only demonstrated the growing prevalence of osteoporosis in patients undergoing total joint replacement (TJR) but may also indicate a significant gap in screening and treatment of this comorbidity. Osteoporosis negatively impacts bone in multiple ways beyond the mere loss of bone mass, including compromising skeletal regenerative capacity, architectural deterioration, and bone matrix quality, all of which could diminish implant fixation. Recent findings both in preclinical animal models and in clinical studies indicate encouraging results for the use of osteoporosis drugs to promote implant fixation. Implant fixation in osteoporotic bone presents an increasing clinical challenge that may be benefitted by increased screening and usage of osteoporosis drugs.

Osteoporotic distal femur fractures in the elderly: peculiarities and treatment strategies

Distal femur fractures account for 4-6% of osteoporosis related fractures of the femur in the elderly population. They represent a relevant cause of morbidity and mortality in the geriatric population with a reported 1-year mortality reaching 30%. Non-displaced fractures or even displaced fractures in patients with high operative risk can be treated conservatively. However, operative treatment is the most widely accepted management option for displaced fractures. The advantage resides in early mobilization and weight-bearing, reducing risks related with a prolonged immobilization when compared with conservative treatment. On the other hand, the intrinsic difficulty of fixing an osteoporotic bone is a major concern. The presence of osteosynthesis devices or prosthetic implants in the femur can make the surgical treatment more challenging, sometimes limiting therapeutic options. Aim of the present paper is to review the most recent literature about osteoporotic distal femur fractures in the elderly, including periprosthetic and other hardware related fractures, to highlight current evidence on management options and related results as a guide for the daily clinical practice.

Periprosthetic fractures of the knee: a comprehensive review

Demographic changes have resulted in an increase in the number of older patients diagnosed with degenerative joint disease. Developments in the field of joint arthroplasty allow a broader population to improve their lifestyles. An increased demand for knee arthroplasty has led to a rise in operations performed worldwide. Although there has been a constant propagation of technology and an increase in medical staffing at a professional level, many patients still encounter complications. Though rare, these factors may lead to life-threatening scenarios and a devastating effect on the success of the operation. One such rare complication includes periprosthetic fractures around the knee, a complex injury which requires a cautious and experienced approach. In this review, we analyze the prevalence, risk factors and classification, investigation and treatment options for periprosthetic fractures with total knee arthroplasty.

Effectiveness of ultrasonographic skeletal muscle assessment in patients after total knee arthroplasty

Objectives

This study aimed to characterize the skeletal muscles of patients who underwent total knee arthroplasty (TKA) using ultrasonography in order to investigate the effectiveness of ultrasonographic skeletal muscle assessment after TKA.

Methods

This study included 50 TKA patients (TKA group) and 41 residents with osteoarthritis who have not received TKA (non-TKA group). Ultrasonography was used to assess the characteristics of several different muscles. Various postoperative outcomes were evaluated. Muscle thickness (MT) and echo intensity (EI) results were compared among operated knees in the TKA group, nonoperated knees in the TKA group, and more severely affected knees in the non-TKA group. For the TKA group, multiple regression was conducted to examine the association between skeletal muscle characteristics of operated knees and postoperative outcomes.

Results

The MTs of the vastus medialis, vastus intermedius, and rectus femoris (RF) were significantly smaller and the RF-EI was significantly greater for both operated and nonoperated knees in the TKA group compared with the non-TKA group (P < 0.017). Several parameters of physical function were significantly poorer in the TKA group than in the non-TKA group (P < 0.05). Multiple regression demonstrated that RF-MT was associated with knee range of motion, knee strength, and physical functional performance in the TKA group (P < 0.05).

Conclusions

The quantity and quality of skeletal muscles were lower in the TKA group than in the non-TKA group. Ultrasonography may be useful for assessing skeletal muscles in TKA patients because MT assessed with ultrasonography was associated with various parameters of physical function.