Tibial fractures represent 1% of all fractures in adults ^[1], accounting for up to 8% of total fractures in geriatric patients ^[2]. Twenty-four percent of tibial plateau fractures occur in patients over 65 years old, typically due to low-energy mechanisms, and are associated with high mortality rates ^[3]. The widespread treatment for these fractures is surgery, as it allows for the restoration of joint congruence, knee alignment, and facilitates a faster patient recovery. The treatment of tibial plateau fractures has traditionally been performed with open reduction and internal fixation (ORIF), which is considered the gold standard technique in young patients, but it has poor outcomes in elderly patients with osteoporosis [4, 5]. In elderly patients, the prevalence of osteoporosis presents a challenge when performing osteosynthesis ^[5]. Therefore, total knee arthroplasty (TKA) has become an alternative treatment in recent years for these complex fractures that are difficult to resolve in elderly patients. Failure rates due to loss of reduction in this patient group range from 30% to 79% ^[5]. Factors that can negatively affect the outcomes of osteosynthesis in the elderly include significant osteoporosis, pre-existing osteoarthritis, comminution, and poor adherence to non-weight-bearing rehabilitation. In addition, the postoperative management of osteosynthesis can be challenging as there is a higher risk of complications due to immobilization, such as muscle mass loss, deep vein thrombosis, pulmonary embolisms, pressure ulcers, and infections, leading to prolonged hospital stays ^[6]. It should not be overlooked that the progression of osteoarthritis following tibial plateau fractures may require a secondary TKA in the long term, becoming a highly demanding process due to the presence of previous scars, stiffness, or ligament insufficiency. The risk of revision in secondary TKA following fracture osteosynthesis varies from 8% to 20% in follow-ups up to 11 years ^[7]. Although there is no consensus on the superiority of total knee prosthesis over osteosynthesis, the advantages of a primary TKA include early joint mobilization, faster rehabilitation, earlier weight-bearing, and a lower reoperation rate since complications such as loss of reduction, poor alignment, or secondary osteoarthritis following osteosynthesis are avoided ^[8]. Therefore, the aim of this study is to assess the functional outcomes of TKA compared to ORIF following tibial plateau fractures in elderly patients.

A retrospective observational review was conducted on 29 patients who underwent surgery for tibial plateau fractures at our center from January 01, 2018 to December 31, 2022. These patients were divided into two comparative groups. Of the 29 patients, 14 underwent TKA as the primary treatment for tibial plateau fractures, and 15 patients underwent osteosynthesis. The inclusion criteria were patients over 50 years of age with an osteoporotic Schatzker type II, III, or IV tibial plateau fracture, with a minimum follow-up of 2 years, and who also had pre-existing osteoporosis, gonarthrosis, or both. This study excluded patients who underwent TKA following distal femur fractures, those with peripheral vascular disease or a history of septic arthritis, patients with open or pathological fractures, and those who had previously undergone open reduction and osteosynthesis. Data collected from both groups included demographic data (sex, age), preoperative data, and patient characteristics (body mass index [BMI], American Society of Anesthesiologists [ASA], fracture mechanism, pre-existing comorbidities, type of fracture according to AO and Schatzker classifications, laterality, pre-existing functionality, pre-existing osteoarthritis), surgical and postoperative data (hospital stay, type of prosthesis used, prosthesis characteristics, need for transfusion, time to surgery, follow-up duration), as well as functional outcomes and associated complications.

Preoperative data

All patients were evaluated preoperatively using X-ray and computed tomography to assess the fracture type and plan the surgery. Knee stability was tested through a physical examination when possible, to evaluate collateral insufficiency.

Surgeries were performed by expert surgeons. The type of treatment (osteosynthesis or prosthesis) and the prosthesis characteristics, constriction, and the use of sleeves or cones were chosen based on the collateral ligaments’ competence, the fracture configuration, the existing bone stock, and the surgeon’s preference.

Surgical techniques

For osteosynthesis, patients were placed in a supine or prone position depending on the approach, on a radiolucent and conventional table, with a tourniquet and prophylactic antibiotics. When the fracture involved the lateral plateau, an anterolateral approach was used. After achieving provisional joint reduction with AK, a locked proximal tibia plate was temporarily used to stabilize the joint and maintain the reduction before inserting the definitive screws. A similar strategy was used for medial plateau fractures.

For prosthetic surgery, patients were placed in a supine position with a tourniquet. Patients received prophylactic antibiotics (2 g Cefazolin). A central incision with medial parapatellar arthrotomy was performed. No osteotomy of the tibial tuberosity was done. Various TKAs were used depending on the fracture characteristics, including posterior-stabilized (PS) prostheses, cruciate-retaining (CR) prostheses, legacy-constrained condylar knee (LCCK) prostheses, or rotating hinge knee (RHK) prostheses. Initially, the tibia was prepared and the cutting line identified to maintain maximum bone stock allowed by the fracture, using the less affected tibial plateau. Cemented prostheses were used in all cases, with varying levels of constraint depending on the collateral ligaments’ insufficiency. Two patients required the use of a cone to address bone stock issues when the defect was larger than 3 mm or deeper than the inferior surface of the tibial component, affecting a third or more of the medial or lateral compartment, and one patient required a 15 mm augment. Bone grafts were added in three patients to increase bone stock and provide greater stability. Extension and flexion gaps were tested after performing the femoral cut.

Postoperative care and follow-up

Drains were removed 24 h post-surgery, and all patients received prophylactic low-molecular-weight heparin to reduce the risk of deep vein thrombosis. Early rehabilitation protocols began on the 1^st day, involving passive and active exercises and early ambulation with a walker if the patient’s condition and lab results permitted. All patients had the same rehabilitation protocol in the TKA group. Postoperative X-rays in anteroposterior and lateral projections were performed, followed by serial radiographs to detect early prosthesis loosening or cannulated screw loosening, consolidation, and alignment assessment. The knee society roentgenographic and scoring system was used to detect early prosthesis loosening. Functional outcomes were assessed based on the final knee flexion-extension degree and the need for walking aids. The knee society score (KSS), developed by The knee society, was used during follow-ups to evaluate surgical outcomes. This scale is divided into a section related to the knee joint and another functional assessment section evaluating the patient’s ability to walk and climb stairs. This scale was performed 1-year post-surgery. Complications such as implant failure, pain, periprosthetic fractures, and infections were monitored during follow-ups at 1 month, 3 months, 9 months, and 1 year in outpatient consultations.

Statistical data

The R-commander v 3.4.3 statistical program for Mac was used for statistical analysis. The Lilliefors test was applied to determine if the parameters followed a normal distribution. The significance level was set at P < 0.05.

TKA group

In the first group, 14 patients underwent TKA. Among them, 13 (93%) were women and 1 (7%) was a man. The patients had a mean age of 76 years and an average BMI of 28.4 (range 20.5–40.5). Six patients had no significant medical history, four had diabetes mellitus, three had a history of heart disease, and one had rheumatoid arthritis. All patients were independent in basic daily activities and ambulated without aids. 29% of patients (4 patients) had documented pre-existing gonarthrosis (Table 1). According to the ASA classification, 7 patients were ASA II (53.8%), 6 patients were ASA III (38.5%), and one patient was ASA I (7.14%). Regarding fracture characteristics, according to Schatzker classification, 42.9% (5 patients) had type II fractures, 35.7% (5 patients) had type III fractures, and 21.4% (3 patients) had type IV fractures. According to the AO classification, one patient had a type B1 fracture, two patients had type B2 fractures, ten patients had type B3 fractures, and one patient had a type C2 fracture. All fractures were closed, occurring in 12 patients (85.7%) due to accidental falls and in 2 patients (14.2%) due to stress fractures in pre-existing gonarthrosis. The most commonly used prosthesis type was PS in 6 patients (42.85%), followed by LCCK in 5 patients (37.5%), RHK in 2 patients (14.28%), and CR in 1 patient (7.14%) (Fig. 1). Nearly half of the cases included patella prosthetics, and two patients (14.28%) required supplements (cones). The average hospital stay was 16 days, with the longest stay being 59 days and the shortest 4 days. The average time to surgery was 6.4 days (range 0–16). The mean surgical time was 120 min. Four patients required red blood cell transfusions. Two patients (14.28%) experienced complications, including a wound dehiscence and a periprosthetic fracture requiring reoperation. The mean follow-up time for this group was 27.8 months.

Osteosynthesis (ORIF) group

In the second group of 15 patients, 10 patients (66.6%) were women and 5 patients (33.4%) were men. The mean age was 68 years with an average BMI of 27.8 (range 22–35). 26.6% of patients (4 patients) had no significant medical history. The most common medical history was diabetes mellitus in 2 patients, followed by 2 patients with kidney transplants, 3 patients with cancer, and 2 patients with a history of heart disease. All patients were independent in basic daily activities and were able to walk without aids. According to the ASA classification, 7 patients were ASA II (53.8%), 6 patients were ASA III (38.5%), and one patient was ASA I (7.14%). According to Schatzker classification, the most common fracture type was type IV (53.3%), followed by type III in 4 patients and type II in 3 patients. According to the AO classification, the most common fracture type was C2 (40%), followed by type B2 in 5 patients (33.3%) and type B3 in 4 patients (26.6%). The most common osteosynthesis method used was a plate in 33.3% of cases, followed by two plates in 26.6%, and a combination of plate and screws or cannulated screws. For approaches, a single approach was used in 9 cases (60%), while two approaches were used in 40% of cases. A posteromedial approach was used in 7 patients, an anterolateral approach in 5 patients, a lateral approach in 3 patients, and a medial approach in 2 patients. Bone grafting was required in 6 patients (40%), with 4 patients receiving hydroxyapatite, 1 patient receiving crushed bone graft, and 1 patient receiving lyophilized bone graft. The average hospital stay was 12 days, with the longest stay being 24 days and the shortest 4 days, and no significant differences were observed (P = 0.18). The average time to surgery was 7.8 days (range 2–21). The mean surgical time was 130 min, with no significant differences seen between both groups (P = 0.13). In two cases, this time was extended due to prior external fixation. Four patients (26.6%) experienced complications during follow-up: one patient required removal of osteosynthesis material and later TKA, one patient had screw extrusion, one required a skin graft using a flap, and one patient later underwent TKA due to osteoarthritis. The mean follow-up time was 26 months.

Functional outcomes

Regarding functional outcomes, 12 patients (85.7%) in the TKA group were able to walk without aids, and only two patients required either crutches or a walker. In this group, 53.3% of patients (8 patients) had complete joint range of motion, and none had knee flexion <90° (Table 2). In the ORIF group, 13 patients (86.6%) ambulated without any aids. In this group, 73.3% of patients (11 patients) had complete joint range of motion, and only one had knee flexion <90° with a 5° extension limitation. There were four deaths (13.79%); two in the TKA group and two in the ORIF group, unrelated to the surgery. Regarding the KSS knee score and KSS function score, 12 patients in the TKA group (85.5%) and 13 patients in the ORIF group (86.6%) were surveyed 1-year post-surgery. Significant differences were found between the KSS knee score for TKA and ORIF (P = 0.01) and in the KSS function score, with better functional values in the TKA group compared to the ORIF group (P = 0.034) (Fig. 2). Similar differences were observed in the WOMAC scores, with a score of 74.6 for TKA and 69.5 for ORIF (P = 0.03). No significant differences were observed in the probability of complications regardless of whether the patients underwent TKA or ORIF (P = 0.6).

Treating tibial plateau fractures in elderly patients presents a therapeutic challenge due to poor bone quality, pre-existing osteoarthritis, and associated comorbidities. The optimal treatment approach for these patients remains controversial. Traditionally, these fractures have been managed with ORIF. However, as demonstrated in Ali et al.’s study, elderly patients with osteoporosis show a high rate of fixation failure, up to 79%. Factors such as fracture comminution, pre-existing osteoarthritis, and non-compliance with weight-bearing recommendations were significantly associated with loss of reduction. Nonunion and post-traumatic osteoarthritis can lead to secondary surgeries, including conversion from ORIF to TKA. The incidence of post-traumatic osteoarthritis varies from 21% to 44% in various studies, and conversion rates to TKA can reach 7.3% at 10 years. Secondary TKA surgeries post-ORIF are technically challenging, with a higher risk of complications and poorer functional outcomes. In our cohort, 29% of patients undergoing TKA had pre-existing gonarthrosis, compared to 20% in the ORIF group. Two patients (13%) from the ORIF group required subsequent TKA, consistent with literature findings. When choosing the implant type and degree of constraint for TKA, preoperative ligament stability must be considered, along with the necessity for allografts or supplementary components such as cones or sleeves. In cases of significant ligamentous instability, constrained or hinged prostheses are required. In our cohort, 50% of patients required either constrained condylar knee prostheses (35.7%) or hinged prostheses (14%), similar to other studies reporting up to 45% need for high constraint. Regarding bone defect management, the use of cones can maintain the support areas for TKA in cases of significant bone loss. In Schatzker Type III fractures, graft or cement augmentation is often sufficient, whereas Type IV fractures frequently necessitate cones or sleeves. In our study, 21% required allografts, 7% needed supplementary components, and 14% used cones to enhance stability due to bone deficits. Approximately half of our patients underwent patella prosthetization, though literature lacks consensus on its necessity. Cemented prostheses are recommended for better long-term outcomes in these patients, which was implemented in all our TKA cases. Primary TKA in acute settings offers immediate stability and allows early weight-bearing, unlike ORIF. Our TKA patients commenced full weight-bearing on average 2 days postoperatively, facilitating early mobility and reducing the risk of immobilization-induced sarcopenia. Complication rates in literature range from 8% to 42%, with the most common issues being surgical wound problems and superficial infections. In our TKA cohort, one patient experienced wound dehiscence and another had a periprosthetic fracture. We found no significant differences in complication probabilities between TKA and ORIF groups (P = 0.06), consistent with other studies. Mortality rates were similar between groups and unrelated to surgery. Regarding functional outcomes, our cohort showed significant differences between the KSS knee score in patients undergoing TKA and ORIF (P = 0.01), as well as in the KSS function score (P = 0.034). These findings are similar to those of Sabatini et al. ^[19], where better functional outcomes were obtained in TKA compared to ORIF in terms of the KSS knee score (P < 0.005) and the KSS function score (P < 0.005), as well as Abdelbadie et al. ^[13]. This also correlates with what has been observed in other studies where high KSS knee score values are obtained in patients undergoing TKA [8, 24, 25]. It is important to highlight the limitations of this study, as it is a retrospective review of patients, and the cohort size is small. Although the inclusion and exclusion criteria were carefully chosen, there is some heterogeneity in the fractures. However, it is important to note that the indications for TKA as an initial treatment for tibial plateau fractures are limited. More prospective studies with larger sample sizes are needed to confirm these findings.

TKA is a viable alternative to ORIF for treating tibial plateau fractures in elderly patients, offering early weight-bearing and rehabilitation with superior functional outcomes. There were no significant differences in complication rates between TKA and ORIF treatments. Further prospective studies with larger sample sizes are needed to confirm these findings.

TKA is a viable alternative to ORIF for treating tibial plateau fractures in elderly patients and allows early rehabilitation.