Introduction. Plate fixation for distal femoral fractures is a commonly used method of fracture stabilisation. Many orthopaedic surgeons traditionally do not allow their patients to weight bear for the first 6 weeks after surgery, fearing of loss of fracture reduction and metalwork failure. The aim of this study is to investigate whether the post-operative weight bearing status after plate fixation influences the outcome in terms of loss of reduction and metalwork failure. Materials & Methods. A retrospective data collection from all patients who treated in our hospital surgically for distal femoral fractures, from January 2015 until June 2017. Inclusion criteria were the operative treatment of these fractures with plate fixation. Patients who were treated with retrograde nail, primary total knee replacement or screw fixation were excluded from the study. Patient, injury and surgery demographic data was collected. The immediate post-operative weight bearing status of these patients was noted. Weight bearing status was divided into two groups – Group 1 (Non and touch weight bear – the non-weight bearing group) and Group 2 (Weight bear as tolerated / Full weight bear – the weight bearing group). Radiological data about fracture displacement or metalwork failure was collected at the six weeks and three months follow up after the operation, using a standardised measurement for displacement performed independently by two authors (EI, TA). Results. Of 70 patients, a total of 51 fractures treated with plate fixation were included to the study. The mean age of the cohort was 64.3 ±20.7 years with the majority of the patients being female (63%). Most of the patients (40%) had a complete articular distal femoral fracture, AO Type 33C. Thirty-nine patients (76%) were treated with one lateral distal femoral plate. The total number of the patients in group 1 was 32 (68%); with 17 patients (32%) in group 2. The weight bearing status did not correlate with the fracture type or the fixation type (p>0.05). None of the 6 weeks follow up radiographs revealed fracture displacement in both study groups. Four of the patients from the non-weight bearing group had >1mm displacement at the 3 months' follow-up radiographs. Fisher's exact test revealed no statistically significant difference between the two study groups in both follow-up time points (p=0.55). Two of the patients in the non-weight bearing group had their plate broken at the 3 months follow up and required revision fixation. Conclusion. By reviewing the outcomes in terms of fracture displacement and metalwork failure following plate fixation of distal femoral fractures, early weight bearing of these patients do not jeopardise the outcome of the operation

The aim of the study was to describe the failure rate of locking plates used for internal fixation of distal femoral fractures and to identify independent predictors of failure.

A consecutive series of 147 patients presenting to the study unit during an 8 year period with a distal femoral fracture were identified from a prospectively compiled trauma database. There were 117 females and 30 males, with a mean age of 70.7 years (13 to 99 years), of which 77 were periprosthetic fractures and 70 were supracondylar fractures around native knees.

There were 35 failures of fixation. The commonest cause was non-union (n=31). The survival of the plate 2 years post-surgery was 74percnt; (95percnt; CI 64percnt; to 84percnt;), which remained static to a mean follow of 5 years. There was no difference in failure of fixation according to gender (p=0.32) or if there was a periprosthetic fracture (p=0.8). Younger age (61.8 vs. 73.6 years, p=0.004), increasing level of comorbidity (p=0.02), and fracture comminution (p=0.001) were all significant predictors of failure of fixation. Cox regression analysis confirmed younger age (p=0.04), increasing comorbidity (p=0.002), and fracture comminution (p=0.002) as independent predictors of failure of fixation and non-union after adjusting for confounding.

The failure of locking plates for distal femoral fractures occurs in more than one in five patients. The independent predictors could be used to identify those patients at greatest risk of failure of the locking plate, who may benefit from alternative methods of fixation, primary bone grafting, or interventions that may aid union.

Aims

The purpose of this study was to determine the weightbearing practice of operatively managed fragility fractures in the setting of publically funded health services in the UK and Ireland.

Aims

Fractures of the distal femur can be challenging to manage and are on the increase in the elderly osteoporotic population. Management with casting or bracing can unacceptably limit a patient’s ability to bear weight, but historically, operative fixation has been associated with a high rate of re-operation. In this study, we describe the outcomes of fixation using modern implants within a strategy of early return to function.

Periprosthetic femur fracture (PPF) are heterogeneous, complex, and thought to be increasingly prevalent. The aims were to evaluate PPF prevalence, casemix, management, and outcomes. This nationwide study included all PPF patients aged >50 years from 16 Scottish hospitals in 2019. Variables included: demographics; implant and fracture factors; management factors, and outcomes. There were 332 patients, mean age 79.5 years, and 220/332 (66.3%) were female. One-third (37.3%) were ASA1-2 and two-thirds (62.3%) were ASA3+, 91.0% were from home/sheltered housing, and median Clinical Frailty Score was 4.0 (IQR 3.0). Acute medical issues featured in 87/332 (26.2%) and 19/332 (5.7%) had associated injuries. There were 251/332 (75.6%) associated with a proximal femoral implant, of which 232/251 (92.4%) were arthroplasty devices (194/251 [77.3%] total hip, 35/251 [13.9%] hemiarthroplasty, 3/251 [1.2%] resurfacing). There were 81/332 (24.4%) associated with a distal femoral implant (76/81 [93.8%] were total knee arthroplasties). In 38/332 (11.4%) there were implants proximally and distally. Most patients (268/332; 80.7%) were treated surgically, with 174/268 (64.9%) requiring fixation only and 104/268 (38.8%) requiring an arthroplasty or combined solution. Median time to theatre was longer for arthroplasty versus fixation procedures (120 vs 46 hours), and those requiring inter-hospital transfer waited longer (94 vs 48 hours). Barriers to investigating PPF include varied classification, coding challenges, and limitations of existing registries. This is the first study to examine a national PPF cohort and presents important data to guide service design and research. Additional findings relating to fracture patterns, implant types, surgeon skill-mix, and outcomes are reported herein

Aims. Dual plating of distal femoral fractures with medial and lateral implants has been performed to improve construct mechanics and alignment, in cases where isolated lateral plating would be insufficient. This may potentially compromise vascularity, paradoxically impairing healing. This study investigates effects of single versus dual plating on distal femoral vascularity. Methods. A total of eight cadaveric lower limb pairs were arbitrarily assigned to either 1) isolated lateral plating, or 2) lateral and medial plating of the distal femur, with four specimens per group. Contralateral limbs served as matched controls. Pre- and post-contrast MRI was performed to quantify signal intensity enhancement in the distal femur. Further evaluation of intraosseous vascularity was done with barium sulphate infusion with CT scan imaging. Specimens were then injected with latex medium and dissection was completed to assess extraosseous vasculature. Results. Quantitative MRI revealed a mean reduction of 21.2% (SD 1.3%) of arterial contribution in the lateral plating group and 25.4% (SD 3.2%) in the dual plating group (p = 0.051); representing a mean decrease in arterial contribution of 4.2%. The only significant difference found between both experimental groups was regionally, at the lateral aspect of the distal femur with a mean drop in arterial contribution in the lateral plating group of 18.9% (SD 2.6%) versus 24.0% (SD 3.2%) in the dual plating group (p = 0.048), representing a mean decrease in arterial contribution of 5.1%. Gross dissection revealed complete destruction of periosteal vessels underneath either medial or lateral plates in both groups. The network of genicular branches contributing to the posterior and distal femoral condyles was preserved in all specimens. A medial vascular pedicle was found dividing from the superficial femoral artery at a mean 12.7 cm (SD 1.7) proximal to the medial epicondyle and was undisrupted in the dual plating group. Conclusion. Lateral locking-plate application resulted in mean 21.2% reduction in distal femur vascularity. Addition of medial plates did not further markedly decrease vascularity. As such, the majority of the vascular insult occurred with lateral plating alone. Supplemental medially based fixation did not lead to marked devascularization of the distal femur, and should therefore be considered in the setting of comminution and poor bone stock in distal femoral fractures. Further clinical research is required to confirm the results of this study. Cite this article: Bone Joint J 2020;102-B(4):530–538

We hypothesised that an independent Notch Trial is essential on the same lines as other Component Trials-Femoral, Tibial and Patellar - in posterior stabilised total knee arthroplasty. Therefore we evolved Notch Trial to visually ascertain the adequacy of intercondylar resection and eliminate the possibility of femoral intercondylar fractures. We undertook a retrospective study to evaluate Notch Trial by the frequency of the need to remove osteophytes or file uneven surfaces in intercondylar resection by using the detachable box part of the trial femoral component, assess occurrence of distal femoral intercondylar fractures and demonstrate Notch Trial in posterior stabilised total knee replacement. We studied 206 patients, 113 females and 93 males, who underwent consecutive primary posterior stabilised total knee replacements applying Notch Trial between 2000 and 2008 in a District General Hospital under our team. Outcome Measurements were 1) frequency of the need to remove osteophytes or file uneven surfaces in intercondylar resection and 2) occurrence of distal femoral intercondylar fractures intraoperatively or on postoperative radiographs. We had to remove the osteophytes and file the cut surfaces in 183 (88.88%) of patients after Notch Trial. We had no distal femoral intercondylar fractures intraoperatively or on postoperative radiographs. Notch Trial allows the surgeon to directly visualise and ascertain the adequacy and precise fit of femoral notch cut with cam part of femoral component to ensure a press fit femoral component in condylar posterior cruciate substituting total knee replacement. Notch Trial prior to Femoral Component Trial effectively pre-empts intraoperative distal femoral intercondylar fractures. We recommend that Notch Trial should become part of the protocol for cruciate substituting total knee replacement and implants of all companies should have the option of a detachable box component for Notch Trial

The objective of this study was to compare differences in alignment following robotic arm-assisted bi-unicompartmental knee arthroplasty (Bi-UKA) and conventional total knee arthroplasty (TKA). This was a prospective, randomised controlled trial of 70 patients. 39 TKAs were implanted manually, as per standard protocol at our institution, and 31 Bi-UKA patients simultaneously received fixed-bearing medial and lateral UKAs, implanted using robotic arm-assistance. Preoperative and 3-month postoperative CT scans were analysed to determine hip knee ankle angle (HKAA), medial distal femoral angle (MDFA), and medial proximal tibial angle (MPTA). Analysis was repeated for 10 patients by a second rater to validate measurement reliability by calculating the intra-class correlation coefficient (ICC). Mean change in HKAA towards neutral was 2.7° in TKA patients and 2.3° in Bi-UKA patients (P=0.6). Mean change in MDFA was 2.5° for TKA and 1.0° for Bi-UKA (P<0.01). Mean change in MPTA was 3.7° for TKA and 0.8° for Bi-UKA (P<0.01). Mean postoperative MDFA and MPTA for TKAs were 89.8° and 89.6° respectively, indicating orientation of femoral and tibial components perpendicular to the mechanical axis. Mean postoperative MDFA and MPTA for Bi-UKAs were 91.0° and 86.9° respectively, indicating a more oblique joint line orientation. Inter-rater agreement was excellent (ICC>0.99). Early functional activities, according to the new Knee Society Scoring System, favoured Bi-UKAs (P<0.05). Robotic arm-assisted, cruciate-sparing Bi-UKA better maintains the natural anatomy of the knee in the coronal plane and may therefore preserve normal joint kinematics, compared to a mechanically aligned TKA. This has been achieved without significantly altering overall HKAA

Aims

The aim of this study was to describe the management and associated outcomes of patients sustaining a femoral hip periprosthetic fracture (PPF) in the UK population.

Aims

The aim of this study was to investigate the rate of revision for distal femoral arthroplasty (DFA) performed as a primary procedure for native knee fractures using data from the Australian Orthopaedic Association National Joint Arthroplasty Registry (AOANJRR).

Aims

Postoperative malalignment of the femur is one of the main complications in distal femur fractures. Few papers have investigated the impact of intraoperative malalignment on postoperative function and bone healing outcomes. The aim of this study was to investigate how intraoperative fracture malalignment affects postoperative bone healing and functional outcomes.

Background:. Septic arthritis following intra-capsular penetration of the knee by external fixation devices is a complication of traction/fixation devices. This study aimed to demonstrate the capsular attachments and reflections of the distal femur to determine safe placements of wires. Methods:. The attachments of the capsule to the distal femur were measured in cadaveric knees. Medially and laterally measurements were expressed as percentages related to the maximal AP diameter of the distal femur. Results:. Mean distance of the anterior attachment was 79.5mm (Range 48.1–120.7mm). The medial capsular reflections were attached an average of 57% back from the anterior edge (Range 41–74%). Laterally the capsular reflections were attached an average of 48% from the anterior reference point (Range 33–57%). Discussion:. Capsular reflections varied. Medially the capsule attachment was up to 74% of diameter of distal femur at the level of the adductor tubercle. Therefore, the insertion of distal femoral traction pins or similar should be placed proximal to the adductor tubercle and no further than 25% of the distance to the anterior cortex. Care is needed to ensure pins do not travel to exit too anteriorly on the lateral side as capsular attachments were found to be up to a distance 48% of the diameter of the femur from anterior reference point

The 8-plate (Orthofix, SRL, Italy) is a titanium extraperiosteal plate with 2 screws which acts as a hinge at the outer limits of the physis. It has been used for correction of both angular and sagittal deformity around the knee. To our knowledge this is the first study describing the use of 8-plates in leg length discrepancy (LLD) correction. We aimed to evaluate outcomes of temporary 8-plate epiphysiodesis in LLD, and to assess the complications associated with its usage. This retrospective study included 30 patients between 2007 and 2010 whom underwent 8-plate epiphysiodesis to address LLD. Leg length measurements were recorded using erect full leg length scanograms and comparison made between pre-operative, interval and final scanograms. Any deviations of the mechanical axis were also recorded. During the study period 34 epiphysiodeses were performed on 30 patients. There were 17 males and 14 females. The average age at the time of procedure was 10.7 years (range 3–15). Average time to final follow-up was 24 months (range 52–10). The average pre-operative LLD was 2.5 cm (range 1.5–6 cm). The mean overall rate of correction was 1.0 cm per year. The mean residual LLD at end of treatment was 1.1 cm (range 0–4.5 cm). Two patients experienced genu recurvatum deformity. This was associated with placement of distal femoral plates anterior to the mid-lateral line. Based on our experience 8-plate epiphysiodesis is a reversible, minimally invasive procedure with reliable results in length correction. However, careful device placement is required to prevent deformity

We present our results of cementless total hip arthroplasty with a tapered, rectangular stem made of titanium-aluminum-niobium alloy. This implant is used since 1979 with only minor modifications. The design of the femoral component achieves primary stability through precision rasping and press-fit implantation. Between October 1986 and November 1987, two hundred consecutive patients (208 hips) underwent total hip arthroplasty with this tapered, rectangular stem. In all cases the acetabular component was a threaded cup made of titanium. At a minimum follow-up of twenty years eighty-seven patients were still alive. Sixty-seven patients (69 hips) were available for clinical and radiographic follow-up. The probability of survival of the stem was 0.96 (95% confidence interval, 0.91 to 0.98) and that of the cup was 0.72 (0.62 to 0.80). The probability of survival of both the stem and the acetabular component with revision for any reason as the end point was 0.71 (0.61 to 0.78). Two stems have been revised due to aseptic loosening. We found various degrees of osteolysis around the acetabular and femoral component (61,7%). At the time of the 20-year follow-up no stem was deemed at risk for loosening. The key findings of our twenty-year follow-up are the very low rate of revisions of the femoral component and the low rate of distal femoral osteolysis associated with this stem. Our data show that femoral fixation of the stem continues to be secure at a follow-up of twenty years

Background. In poliomyelitis; hand to knee gait is the sum of quadriceps weakness and fixed knee flexion deformity. Limb shortening is another added problem. Usually, each problem is attacked separately; with variable end results and complication rates for each procedure. Patients and methods. 22 patients (16–46 y.); with poliomyelitis with hand to knee gait due to fixed knee flexion deformity of mild to moderate degree (10–400); and limb shortening of 4.5–9.5 cm., were managed simultaneously by a single operation. A distal femoral metaphyseal anterior closing wedge (recurvatum) corrective osteotomy was done to treat acutely the fixed knee flexion deformity(and subsequently hand to knee gait). A modified Wagner or Orthofix frame was applied as a mono-plane mono-axial lengthening device to stabilize the osteotomy and to lengthen the short limb. Lengthening was started in all cases two weeks post-operatively. Results. All cases showed full correction of the deformity with elimination of the hand to knee gait problem and all showed - the desired - limb length equalization. The femora were lengthened to an average of 6.4 cm.(= 21% of original femoral bone length), range of lengthening was: 4–9 cm. (= 11–26%). The average healing index was 37 days per centimeter (with a range of 31 to 53 days per centimeter.). Conclusion. Simultaneous management of hand to knee and limb shortening could be achieved by a single osteotomy which is used to extend the knee acutely and for distraction two weeks later using a mono-lateral frame. Results were good, complications were few and accepted and the procedure is well tolerated by the patients

The reconstruction of lower limb defects after oncological reconstructions is still a problem in limb salvage surgery. Large bony defects need to be treated with sound and durable reconstructions. During recent decades, the life expectancy of patients affected with cancer has improved considerably because of advances in chemotherapy, immunotherapy, hormonal treatment and radiotherapy. This improvement requires greater reliability in the reconstructive procedure in order to avoid mechanical failure during prolonged survival of the patient. The author experience with modular megaprosthesis by Link (megasystem C) allowed us to present a rapid, effective and functional solution. From June 2001 to December 2007 225 patients have been operated with a megaprosthesis C for tumoral resection. The new megaprosthesis C by Link represents a wide-ranging system that can afford a large variety of reconstructions in the inferior limb, from very short replacement of 5 cm in proximal femur, to a total femur and proximal tibia replacement. Modularity is represented by 1 cm increase in length. The different options of cemented and not cemented stem may be used with intraoperative decision. In cemented stem a rough collar seals the osteotomy and prevents polyethylene debris from entering the femoral canal by inducing a scar tissue around the stem entrance (so-called purse-string effect). Moreover in patients with solitary lesions and very good prognosis an allograft-prosthesis composite can be performed with improved clinical results on walking and function. Of the 225 patients that underwent tumoral resection and reconstruction with a modular megaprosthesis approximately 43% (97 cases) were operated for metastatic disease. Among these cases 55 cases were proximal femoral recontructions, 39 cases were distal femoral reconstructions and 3 cases were proximal tibial reconstructions. All cases were performed with cemented stems. We experienced a 7% of postoperative infections, 2% of dislocations of proximal femoral prosthesis and 3% of mechanical failures. While infections and dislocation rates were in the average for this surgery, mechanical failures were relatively high. We should consider that in patients with relatively long resections and muscle deficiency the mechanical stress exerted on the prosthesis can explain this kind of mechanical failure. However the new design of morse tapers have annulled these problems

Femoral lengthening has been associated with narrowing of the joint space at the hip. We have studied the joint space before lengthening in 20 patients with a short femur due to a femoral-shaft fracture (15) or distal femoral epiphyseal injury (5). Their mean age at injury was 16 years (3 to 27) and the mean shortening was 5.4 cm (1.1 to 14). We found that the hip joint space of the shortened femur was significantly narrower (p < 0.001) than that on the normal side, with a mean narrowing ratio of 15.5% (−5 to +43). The narrowing ratio was directly related to the period spent non-weight-bearing (p < 0.001), but not to the amount of femoral shortening. We have shown that the joint space of the hip in patients with post-traumatic femoral shortening was narrowed even before femoral lengthening had been started

Introduction. Malrotation following total knee replacement is directly related to poor outcome. The knowledge of proximal and distal rotational axes and angles of the femur is therefore of high importance. The aim of the study was to determine whether the most used proximal and distal femoral angles; femoral anteversion angle (FAA) and posterior condylar angle (PCA) were different within individuals, between right, left and gender. As well, we studied whether the “inferior condylar angle” is correlated to the PCA and therefore useful in determining the rotation of the distal femur. Material and Methods. From 36 cadavers the femora were obtained and after removing the soft tissue a Computed Tomography (CT) scan was made. Three angles were measured: (i) the FAA between femoral columnar line (FHNL) and posterior condylar line (PCL), (ii) the PCA between anatomical transepicondylar line (TEL) and PCL, (iii) the inferior condylar angle (ICA) between the TEL and inferior condylar line (ICL). Statistical analysis of comparative relationships between the different angles was examined by calculating correlation coefficients and a paired t-test. Results. The mean FAA, PCA and ICA for the whole group were respectively 12.0 degrees (range 0.2–31.6, SD 8.3, 95% CI 9.6–14.4), 4.8 degrees (range 0.9–9.6, SD 2.3, 95% CI 4.1–5.4) and 4.5 degrees (range 0.1–9.8, SD 2.1, 95% CI 3.9–5.1). A strong correlation of the FAA was found within the total group and left versus right (r = 0.82; p = 0.00). A weaker relationship was found for the total group of the PCA measurements (r = 0.59; p = 0.00). When FAA compared to the PCA subdivided in only sexes, there is a weak correlation for the female group (r = 0.54; p = 0.00) Despite the small mean difference of the mean ICA and PCA, there was no correlation between these two angles. Conclusion. Considering the weak correlation of the FAA and PCA within the group but also individuals, the importance of development of more individual approaches for determining the optimal rotation of the components in total knee surgery is essential. As a result, one should be aware that the widely used, current guidelines for knee rotation of 3 degrees of external rotation in placing total knee arthroplasties shows variation between individuals. A more individual approach in total knee arthroplasty seems essential for future knee prosthesis implantations

Background. Adequate rotation of femoral component in total knee arthroplasty(TKR) is mandatory for preventing numerous adverse sequelae. The transepicondylar axis has been a well-accepted reference for femoral component rotation in the measured resection technique. In this technique, measured resection is performed referenced off the tibial cut - perpendicular to the tibial mechanical axis with the knee in 90 ° of flexion. However, to the best of our knowledge, it is not known whether this technique apply well to a knee with tibia vara. This study evaluates the reliability of the transepicondylar axis as a rotational landmark in knees with tibia vara. Methods. We selected 101 osteoarthritis knees in 84 symptomatic patients(mean age: 69.24 ± 5.68) with proximal tibia vara (Group A). Group A was compared with 150 osteoarthritic knees without tibia vara in 122 symptomatic patients (mean age: 69.51 ± 6.01) (Group B). The guide line for selection of all these knees were based on the degree of tibia vara angle (TVA) which was formed by line perpendicular to epiphysis and by anatomical axis of the tibia - all measured in radiographs of the entire lower limb. Magnetic resonance imaging (MRI) axial images with most prominent part of both femoral condyles were used for measurement of transepicondylar axis(TE), anteroposterior axis(AP) and posterior condylar axis(PC). Results. The mean TVA of group A was 8.94° ± 3.11 and group B was 1.24° ± 0.85. The TE line in Group A showed 6.09 ° ± 1.43 of external rotation, relative to PC. This did not show statistical difference compared with 5.95 ° ± 1.58 in Group B (p=0.4717). The AP line in Group A showed 6.06 ° ± 1.93 of external rotation, relative to the line perpendicular to PC. This was statistically significant when compared to 5.44 ° ± 2.13 in Group B (p=0.020). Conclusion. There is no difference between knees without tibia vara compared those with tibia vara with regards to transepicondylar axis. In addition, both groups have almost identical external rotation of approximately 6 °. The AP axis was only approximately 0.5 ° difference between the two groups. The distal femoral geometry was not affected by tibia vara deformity, that is, there were no hypoplastic or hyperplastic deformities of medial femoral condyle in osteoarthritic knees with tibia vara. The use of transepicondylar axes in determining femoral rotation may produce flexion asymmetry in knees with proximal tibia vara. So, It should be pointed out that more attention should be paid on femoral component rotation and flexion gap balancing in knees with proximal tibial vara

Background. Computer-assisted navigation systems for total knee arthroplasty (TKA) were introduced to improve implantation accuracy and to optimize ligament balancing. Several comparative studies in the literature confirmed an effect on the component position and other studies could not confirm these results. For ligament balancing most studies found no significant influence on the clinical outcome using a navigation system for TKA. In the literature there were no reports of mid-term results after navigated TKA. With our study we wanted to show if the use of a navigation system for TKA will have an influence on the component's position and on the clinical results at 5-year follow up. Methods. We enrolled 200 patients in a prospective randomized study with a minimum follow up of 5 years. 100 TKA were operated on without using a navigation system (Group A) and 100 surgeries (Group B) were done with computer assistance. Radiological investigation by standard radiographs including a long-leg X-ray was performed with a follow up rate in Group A of 86.2% versus 80.2% in Group B. We measured the mechanical axis of the leg, lateral distal femoral angel (LDFA), medial proximal tibial angle (MPTA), tibial slope and the alpha-angle of the patella. Clinical investigation was performed with a follow up rate in Group A of 85.7% versus 79.8% in Group B including the parameters for the range of motion (ROM), ligament balancing, anterior drawer test, feeling of instability, anterior knee pain, effusion, WOMAC Score, Insall Score and HSS Knee Score. Results. In both groups there was no aseptic loosening or difference in TKA survival rate (Group A 95.4% versus Group B 98.85% 5-year survival rate, p = 0.368). With the navigation technique the mechanical axis of the limb in the frontal plane was improved (p = 0.015; Group B: 1.67 ° ± 1.6° versus 2,44 ° ± 2.2 ° in Group A). 90% of the Group B and 81% of the Group A were within 3 ° varus/valgus deformity of the mechanical axis of the limb (p = 0.157). The accuracy of tibial slope was higher in the Group B (p = 0.001). More patients of the Group B (95% versus 79%) were within a deviation of 3 °, −7 ° tibial slope (p = 0.007). The mean deviation of 90 ° LDFA was higher (p = 0.034) in the Group A (1.89 ° versus 1.36 ° in Group B). Mean deviation of 90 ° MPTA, mean MPTA, mean LDFA and patella alpha angle were similar in both groups (p 0.253). There was no difference in ROM, ligament balancing, anterior drawer test, anterior knee pain or feeling of instability (p 0.058). Insall Knee Score total (181 Group A/191 Group B) and HSS Knee Score total (91 Group A/93 Group B) was higher with the navigated procedure in Group B (p 0.026). WOMAC total and HSS grades were similar in both groups (p 0.070). Conclusions. The accuracy of the mechanical axis of the limb and the tibial slope was higher with the navigated procedure. TKA survival rate and clinical outcomes were similar in both groups at 5-year follow up