An evaluation of subtalar titanium screw arthroereisis for the treatment of symptomatic paediatric flatfeet - early results.

BACKGROUND: Idiopathic flexible flatfoot is a common condition in children which typically improves with age and remains asymptomatic. However, the condition can sometimes be more severe, and cause mechanical impairment or pain. The aim of the study was to perform a prospective clinical, radiological, podoscopic and pedobarographic assessment (static and dynamic) of subtalar titanium screw arthroereisis for the treatment of symptomatic, idiopathic, flexible flatfeet. METHODS: A prospective, consecutive, non-controlled, cohort, clinical follow-up study was performed. In total, 30 patients (41 feet), mean age 10 (6 to 16 years), were evaluated. Clinical and standing radiological assessments, static and dynamic pedobarography, as well as podoscopy, were performed before surgery and at final follow-up. RESULTS: Treatment was associated with significant improvements in heel valgus angle, radiographic parameters (lateral and dorso-planar talo-first metatarsal angle, calcaneal inclination angle, talar declination angle, longitudinal arch angle) and podoscopic parameters (Clark's angle, Staheli's arch index and Chippaux-Smirak index). Significant increases were noted for lateral loading, forefoot contact phase and double support / swing phase, and reduced medial loading (dynamic pedobarography), as well as lateral midfoot area and loading, but decreased were observed for medial forefoot loading (static pedobarography). Four patients reported persistent pain in the sinus tarsi region (six feet), and in one case, the implant was replaced for a larger one due to undercorrection. No overcorrections or infection complications were noted in the study group. CONCLUSIONS: Subtalar arthroereisis is a minimally-invasive and effective surgical method for treating symptomatic, idiopathic, flexible flatfeet; it has an acceptable complication rate with good early clinical results. LEVEL OF EVIDENCE: II b.

Clinical and radiological evaluation of radial neck factures in children and adolescents treated by percutaneous leverage reduction with Kirschner wire stabilization.

PURPOSE: The aim of the study was to evaluate the clinical and radiological results of surgical treatment of radial neck fractures in children and adolescents by percutaneous leverage with Kirschner wire stabilization. METHODS: A retrospective clinical and radiographical evaluation was performed on a cohort of 61 patients (mean age 9.7 years; range 3 to 15) with isolated, unilateral radial neck fractures treated between 2009 and 2019. The mean duration of follow-up was 4.2 years (range 2 to 9 years). All fractures were types III and IV according to Judet's classification. RESULTS: After mean follow-up, the radiographic results according to Metaizeau were rated as excellent in 70.5% of respondents, good in 27.9%, satisfactory in 1.6%. According to Mayo Elbow Performance Score, 95.1% of respondents obtained a very good result, 3.3% good, and 1.6% satisfactory. The mean radial neck-shaft angle changed from a mean 51.5° before operation to 3.8° postoperatively (p<0.001). The mean translation was 3.1mm before surgery and 0.5mm postoperatively (p<0.001). No limb axis deviation, elbow joint instability, and infection of the implant insertion site were observed. No statistically significant differences were noted between girls and boys (p>0.05). CONCLUSIONS: Our findings indicate that percutaneous leverage with Kirschner wire stabilization is an effective and safe method for treating isolated radial neck fractures, characterized by a low risk of iatrogenic complications.

Clinical and radiological evaluation of surgical treatment of medial epicondyle fractures of humerus in children. A two-centre study.

The present study analyses the outcome of open reduction and internal fixation (ORIF) of humerus medial epicondyle fracture with the use of Kirschner (K) wires, and determine the effect of elbow dislocation. The study included 112 patients operated on in 2005-2016. Of these, 81presented with an isolated medial epicondyle fracture (mean age 11.6 years), and 31 with an elbow dislocation (mean age 11.9 years). Out of 112 patients tested, 98 achieved an excellent treatment result, ten good and a mean Mayo Elbow Performance Score (MEPS); no significant differences were observed between dislocated and non-dislocated elbow groups. Those with an isolated medial epicondyle fracture demonstrated a mean flexion of 140.7° and extension deficit of 3.0°, while those with an elbow dislocation displayed a mean flexion of 134.5° and extension deficit 6.1°. The dislocation group demonstrated significantly greater extension and flexion deficits (p = 0.019, p < 0.001, respectively). One patient required revision surgery due to nonunion. Ulnar nerve function was normal in 110 patients: in the other two, it resolved spontaneously in one, and the nerve was transposed in the other. Medial elbow instability was found in seven patients: two with elbow dislocation and five without. ORIF with K wires is a safe procedure for treating medial epicondyle humeral fractures that yields good or very good results. Similar outcomes are observed between patients with and without dislocation according to MEPS; however, flexion and extension are more limited in the former group.

An assessment of the return to professional activity of patients aged ≤30 years after hip replacement surgery.

OBJECTIVES: The study evaluated the professional activity of patients after a total cementless hip replacement surgery performed at the age of ≤30 years. MATERIAL AND METHODS: The study group comprised 87 patients, with 95 total cementless hip replacements. The mean age was 25.7 years. The youngest patient was 17 years old, and the oldest 30 years old. The mean length of observation was 20.1 years, ranging 5-33 years. All patients underwent clinical and radiological evaluations before the surgery, and again in the third, sixth and twelfth months after the surgery. Further follow-up visits were performed every year. The tests were scored according to the Merle d'Aubigné and Postel (MAP) classification, as recommended by the Polish Society of Orthopaedics and Traumatology. Postoperative radiographs were used to assess the position of the endoprosthesis, and the degree of implant healing in the bone tissue. The data was subjected to statistical analysis. RESULTS: Of the surveyed group, 67 patients were professionally active before the surgery: 34 were white-collar workers, 29 manual workers, and 4 students or school pupils. The remaining 20 had not worked for many years, and were receiving sickness or disability benefits. An excellent result, according to the Kellgren-Lawrence classification, was noted in 22 cases, a good result in 42 cases, and a satisfactory result in 6 cases. In 25 cases, a poor result was observed. All of the patients professionally active before the surgery returned to work following the procedure. A further analysis found that 15 previously-unemployed patients commenced employment following the procedure. The mean length of the sick leave was 196.2 days, and rehabilitation payments were granted in 5 cases. CONCLUSIONS: Total cementless hip replacement is a valuable method of treating osteoarthritis in young patients. All of the patients who worked before the surgery returned to work in the same position and on the same employment conditions. Most of the previously-unemployed patients commenced employment following the procedure. Int J Occup Med Environ Health. 2021;34(6):747-54.

The return to professional activity patients treated surgically due to advanced gonarthrosis.

OBJECTIVES: The goal of this work is to analyze the issue of return to professional activity by working-age patients who have been treated surgically with total knee arthroplasty (TKA) due to gonarthrosis. MATERIAL AND METHODS: Overall, 88 working-age patients were examined, with a total of 91 TKA procedures performed due to advanced gonarthrosis. The average age of the patients was 54.2 years for women and 58.1 years for men. A modified Knee Society Score scale was used to compile the results of the clinical trial. The Kellgren-Lawrence classification was used to assess preoperative radiographs. Postoperative radiographs evaluated the position of the endoprosthesis of both the femoral and tibial components in the anteriorposterior and lateral upright projections. The obtained results were subjected to statistical analysis. RESULTS: In the preoperative assessment, both the clinical and radiological results obtained were unfavorable in all cases. Throughout the observation period of approximately over 3.8 years, a very good result was noted in 65 cases (71.4%), a good result in 20 cases (22%), and a satisfactory result in 6 cases. There were no bad results. The average improvement on the Visual Analogue Scale was 6.5 pts. The radiological assessment did not reveal any radiological symptoms of the aseptic loosening of the endoprosthesis, simultaneously concluding that each time the endoprosthesis components were properly seated. Only 53 (58.3%) of the examined patients were professionally active before the surgery. After completing the treatment, 46 (50.5%) of all patients returned to work, in favor of intellectual workers. The average duration of sick leave was 136.2 days, and rehabilitation allowance was granted in 19 cases. CONCLUSIONS: Firstly, in working-age patients, TKA is a valuable method for surgical treatment of advanced gonarthrosis of varying etiology. Secondly, most of the patients who worked before the surgery returned to performing work in the position held and on the same full-time equivalent basis. Int J Occup Med Environ Health. 2021;34(5):617-28.

Time efficiency of direct anterior hip arthroplasty compared to postero-lateral approach in elderly patients.

INTRODUCTION: Primary arthroplasty of the hip joint is currently one of the most commonly performed procedures in orthopedics. In Poland we are observing significant changes in the age structure. With the prolonged life more and more elderly patients require musculoskeletal surgery to maintain comfortable and painless mobility. Reducing the duration of the procedure reduces the costs of anesthesiology, surgical and instrument teams, as well as the operating room technical team. The aim of the study was to compare the time required to perform hip joint arthroplasty by the direct anterior approach (DAA) with the postero-lateral approach (PLA) in our hospital. MATERIAL AND METHODS: A retrospective analysis of 559 total and bipolar cemented and cementless hip replacement procedures based on two operative approaches - the minimally invasive DAA over the course of 2 years, and the standard PLA over the course of 3 years - was performed. RESULTS: Statistically significant differences were observed between the approaches used for cementless total arthroplasty with regard to the mean treatment times: 51.9 min for the 272 DAA cases, and 78.3 min for the 190 PLA cases (p < 0.0001). For the cementless hemi-arthroplasty procedure, the mean treatment times were 46.9 min in 36 patients for DAA, and 48.2 min for 61 patients for PLA (p = 0.57). CONCLUSIONS: Minimally invasive DAA significantly shortens the time of the procedure in elderly patients compared to PLA. Further study is needed to analyze other aspects of those two approaches.

Prognosis for Peripheral Nerve Injuries after Hip Joint Arthroplasty.

BACKGROUND: Peripheral nerve damage is a rare complication of hip replacement surgery that severely impairs the therapeutic outcome. The aim of the present study was to determine the time needed for nerve recovery and re-storation of activity following iatrogenic damage during a primary or revision hip arthroplasty from an anterolateral approach and its relationship with the severity of damage. MATERIALS AND METHODS: A prospectively collected database of 1107 patients treated with primary arthroplasty and 303 patients following revision arthroplasty (mean age 63 years, range 53 to 72 years) was analysed. This included 15 cases of palsy of the peroneal branch of the sciatic nerve and 7 of the femoral nerve. The mean follow-up was 3.6 years (minimum two years). RESULTS: The following risk factors were identified: dysplastic osteoarthritis, limb elongation, revision arthroplasty, female sex and post-traumatic osteoarthritis. All five patients demonstrating light palsy (Lovett score 3-5), and 9 out of the 17 with severe palsy (Lovett score 0-2) achieved full recovery. Of all patients, 63.6% regained nerve function after 4 weeks to 24 months (mean 17 months), with nine demonstrating complete recovery and five partial. Also, 66.6% patients regained femoral nerve function and 61.5%, sciatic nerve function. CONCLUSION: 1. The femoral nerve and the peroneal branch of the sciatic nerve demonstrate a similar pattern of functional recovery following damage. 2. All patients recovered from light palsy, and almost 2/3 of cases of severe palsy demonstrated partial or complete recovery. 3. Female sex is a significant risk factor.

Retraction Note: An evaluation of the potential consequences of drilling titanium and tantalum implants during surgery - a pilot study.

The authors have retracted this article [1] because it constitutes redundant publication [2].

Success Rates of Revision Knee Arthroplasty for Periprosthetic Joint Infection in Rheumatoid and Non-Rheumatoid Arthritis Patients.

This study evaluated the success and failure rates as well as the final results following 2-stage revision total knee arthroplasty (TKA) for periprosthetic joint infection (PJI). Particular emphasis was placed on comparing patients with rheumatoid arthritis (RA) and non-RA patients. A total of 140 knees that required 2-stage revision for PJI after TKA were analyzed. Mean patient age at first revision TKA was 67.9 years (range, 43 to 89 years), and mean time from second-stage revision to final follow-up was 53.3 months (range, 26 to 127 months). Thirty-eight of the 140 knees (27.1%) demonstrated recurrence of infection after first 2-stage revision. Of these, 8 required another 2-stage revision, 25 required knee arthrodesis, and 2 required amputation; 3 patients refused further treatment or were lost to follow-up. There was no recurrence of infection. No statistically significant differences were observed between the RA and non-RA groups in terms of success or failure rate (P=.6) according to Diaz-Ledezma and Knee Society Scores (P=.3). These findings indicate reinfection rates and final results were similar in RA and non-RA patients following revision TKA for PJI. [Orthopedics. 2019; 42(5):e472-e476.].

The Influence of Implant Position on Final Clinical Outcome and Gait Analysis after Total Knee Arthroplasty.

The aim of the study was to evaluate the impact of implant component alignment on objective and subjective outcomes after total knee arthroplasty (TKA). The rotation of the femoral component and its influence on the final results were also examined. After exclusion, the study examined 102 patients (mean age, 66.28 years; range, 51-79 years) who had undergone unilateral TKA. All of the operative procedures were performed by one surgeon with one type of implant. One year after the operation, improvements in Knee Society's Knee Scoring System, functional score, Western Ontario and McMaster Universities Osteoarthritis Index, and Visual Analog Scale were observed; however, none showed a significant correlation with any of the parameters analyzed by X-ray or computed tomography (CT) (α, ß, γ, δ angles and posterior condylar angle [PCA]). Significant improvements were found for the vast majority of the parameters used for gate analysis at the final follow-up. Significant correlations were found between PCA angle and differences in stance phase, swing phase of the operated limb, and step width (all p = 0.03). No other significant relationships were found between gait parameters and indicators measured by X-ray and CT. None of the analyzed radiographic parameters, including rotation of the femoral component, correlated with final clinical results. Neither femoral internal rotation of 3° to 6°, nor rotation of 0° ± 3° or 0° ± 6° influenced the outcome. One year after TKA, a significant improvement was observed in both functional and gait parameters.

The Anterolateral Ligament of the Knee: A Proposed Classification System.

The anterolateral ligament (ALL) is a potential stabilizer of the knee and cooperates with the anterior cruciate ligament (ACL). It originates on the lateral epicondyle of the femur, to which it is mainly posterior and proximal; insertion is posterior to Gerdy's tubercle. Its anatomical characteristics vary. Recent publications have focused on morphological variations concerning mainly the femoral and tibial attachments, and on morphometric measurements. Histological and cystochemical examinations have also been performed. Classical anatomical dissection was performed on 111 lower limbs (25 isolated and 86 paired) fixed in 10% formalin. The knee region was dissected using traditional techniques and the morphological features of the ALL were assessed: morphometric measurements and the types of ALL. The ALL was present in 70 individuals (37 woman and 33 men). In 30 cases, it was absent symmetrically, and in 11, it was present on just one side (P = 0.0011). The ALL was morphologically very variable. In type I (the most common form - 64.3%), a single band traveled parallel to the fibular collateral ligament (FCL); in type II the band crossed it. In type III, the origin was located on the lateral epicondyle of the femur and also on the lateral-posterior surface of the joint capsule, and the insertion was in the deep fascia of the leg: this type could be called a capsule. Type IV was characterized by a double ALL, type IIb by ligaments that bifurcated, and type V by the ALL starting directly from the FCL rather than the femoral epicondyle. The ALL is characterized by high morphological variability, both in its femoral and in its tibial attachments and in its course. Clin. Anat. 31:966-973, 2018. © 2018 Wiley Periodicals, Inc.

Treatment of Femoroacetabular Impingement with a Mini-open Direct Anterior Approach.

BACKGROUND: The opinion about best methods of femoroacetabular impingement (FAI) treatment are not consistent. Operative treatment of this condition may be arthroscopic, but open procedures with osteotomy of the greater trochanter and hip dislocation has been used. The present study evaluates the benefits of the mini-open direct anterior approach (DAA) in treating patients with FAI, with is a procedure available for most orthopedic surgeons. MATERIALS AND METHODS: 39 patients treated for FAI (25 men and 14 women) at an average age of 29.3 years (range 18-46 years) were reviewed in this retrospective study. The mean followup was 45 months, (range 24-55 months). The hip impingement test was positive in all patients. The diagnosis of FAI was confirmed on anteroposterior and lateral hip view radiographs. All patients were operated with mini-open DAA. The outcomes were assessed with the Harris Hip Score, Short-Form 36 Health Survey and VAS score. Preoperative osteoarthritis was assessed according to Tönnis score. RESULTS: At the final followup, improvement was noted compared to preoperative status in Harris Hip Score (P < 0.00001), visual analog scale score (P < 0.001), and Short-Form-36 score (P < 0.001). Nineteen patients returned to their previous sports activities. No major complications occurred. One patient developed heterotopic ossification and three patients developed temporary postoperative meralgia paresthetica. Five patients from the treatment group required total hip arthroplasty for severe osteoarthritis. CONCLUSIONS: Mini-open DAA is a safe and effective procedure for the treatment of FAI that gives good relief of symptoms and allows a successful return to preoperative activity levels. Further research with a longer followup period is needed to evaluate the influence of surgery on natural history of FAI.

Return to Work after Surgical Treatment of Coxarthrosis by Total Cementless Hip Arthroplasty.

BACKGROUND: Total hip arthroplasty is currently commonly used in surgical treatment of advanced hip osteoarthritis of various aetiologies. Studies show that the number of these procedures has been growing every year, which is associated with global population ageing. The aim of the study was to assess return to work in patients after surgical treatment by arthroplasty due to hip osteoarthritis. MATERIAL AND METHODS: The study assessed 114 patients of productive age who underwent surgery due to advanced hip osteoarthritis. The mean age was 49.9 years in women and 52.2 years in men. All patients included in this retrospective study underwent clinical and radiographic assessment prior to arthroplasty and at the last out-patient follow-up visit. The patients' occupational status and the time of return to work after surgery were also assessed. The results of this clinical study were analysed according to the Merle d'Aubigne-Postel classification (modified by Charnley). Preoperative radiographs were assessed according to the Kellgren-Lawrence classification. The radiographs served to assess the position of the endoprosthesis, including both the acetabular component and the stem. The results were statistically analysed. RESULTS: Pre-operative assessment classified all cases as poor both clinically and radiographically. The post-operative outcomes were excellent in 71 cases (61.7%), good in 37 cases (32.2%) and fair in 7 cases. No case was classified as poor. The mean improvement was 6.6 points and reached the level of statistical significance. Radiographic evaluation did not reveal evidence of aseptic implant loosening and confirmed a normal seat of endoprosthetic components within the Lewinnek safe zone in each case. Only 75 (65.8%) of the study participants worked before the procedure. After the treatment was completed, 67 (58.8%) study patients took up employment. The mean duration of sick leave was 138.6 days and 21 patients were receiving rehabilitation benefits. CONCLUSIONS: 1. Total hip arthroplasty is a valuable method of surgical treatment of advanced coxarthrosis of various aetiologies in patients of productive age. 2. Most patients who worked before the surgery return to work in the same position and work time. 3. Only dysplastic coxarthro-ses have an unfavourable prognosis with respect to starting or resuming work after surgery.

An evaluation of the potential consequences of drilling titanium and tantalum implants during surgery - a pilot study.

BACKGROUND: The aim of the study was to evaluate the potential consequences of drilling titanium alloy (Ti) and tantalum (Ta) implants. METHODS: During an in vitro study, four holes were made in each of two spatially porous trabecular implants: one Ta and the other Ti alloy (Ti-6Al-7Nb). The weight and the volume of particles produced during the drilling were then measured using a Radwag XA 110/2X (USA) laboratory balance. RESULTS: The loss of mass of the Ti and Ta implants was respectively 1.26 g and 2.48 g, and the volume of free particles was respectively 280 mm3 and 149 mm3. The particles were recovered after each stage. Despite the use of 5 µm filters, around 0.6% of the total implant mass from both implants was not recovered after drilling (roughly 2% of the mass of the particles created). CONCLUSION: It is technically difficult to make holes in Ti and Ta implants using standard surgical tools, and the process creates a significant amount of metal particles which cannot be removed, despite intensive flushing. This may have a potentially adverse influence on the survival of the implant and result in negative systemic consequences.

Short and mid term results of revision total knee arthroplasty with Global Modular Replacement System.

BACKGROUND: The original knee megaprostheses with fixed or rotating hinge articulation were custom made and only used for reconstruction of the knee following distal femoral or proximal tibial tumor resections. The aim of the study was to analyze the short- and mid-term results of revision total knee arthroplasty with Global Modular Replacement System (GMRS) used in difficult situations not amenable to reconstruction with standard total knee replacement implants. MATERIALS AND METHODS: Nine patients (9 knees) were treated with this comprehensive modular implant system, with a mean age of 73.7 years (range 56-83 years) and a mean followup of 5 years (range 3-8 years). Two patients were treated for distal femoral nonunion, five for distal femur periprosthetic fracture and two for periprosthetic joint infection. RESULTS: The mean Knee Society Score: Knee and functional scores were 77.9 and 40 points, respectively. All demonstrated full extension and flexion was at least 90°. Recurrence of infection was present in one patient. No signs of loosening, dislocation, or implant failure were observed. CONCLUSIONS: Based on our small series of patients that represent severe cases, GMRS provides relatively good mid-term functional results, pain relief, and good implant survivorship with a low complication rate. This salvage procedure allows elderly, infirm patients to regain early ambulatory ability.

Two stage revision hip arthroplasty in periprosthetic joint infection. Comparison study: with or without the use of a spacer.

PURPOSE: The aim of this study was to compare two methods of two-stage surgery for PJI (periprosthetic joint infection) after THA (total hip arthroplasty): one with and one without the use of an antibiotic-loaded cement spacer. METHODS: This retrospective study was performed on 99 consecutive patients (99 hips) with a minimum follow-up of 24 months. Patients were divided into two groups: (1) in whom the operation was performed using a spacer, and (2) for whom a spacer was not used. RESULTS: For the whole cohort, the results improved between pre-operative and final follow-up. Recurrence of infection was found in nine out of 98 patients (9.2%) and was not significantly different between the two groups. Patients treated with a spacer had better functional improvement in the interim period, but the VAS score was better in the non-spacer group. The improvement in final function was better in the spacer group with regard to HHS, but not according to WOMAC score or VAS at final follow-up. CONCLUSION: The resection arthroplasty should be awarded particular consideration in cases of poor soft tissue quality, bone stock deficiency, when complications related to spacer use are expected or chances of new hip endoprosthesis implantation are low.

The use of calcium carbonate beads containing gentamicin in the second stage septic revision of total knee arthroplasty reduces reinfection rate.

BACKGROUND: The aim of the study was to analyze effectiveness and safety of packing the medullary canal of the tibia and femur with Herafill (Heraeus Medical GmbH, Wehrheim, Germany), a void filler and antibiotic carrier, during second stage revision total knee arthroplasty (TKA) for periprosthetic joint infection (PJI). METHODS: Two groups were formed of 28 consecutive patients during second stage revision TKA, comparable for gender and age. The study group received Herafill, while the control group did not. The average follow-up was 52 months (minimum 36 months). RESULTS: No reinfections were observed in the study group, while five were seen in the control group. No other differences were observed between the study and control groups, including mean clinical KSS (Knee Society score) (67.4 and 68.4 points, respectively) and functional score (72.5 and 70.5 points respectively). No side effects related to the use of Herafill beads were noted. CONCLUSIONS: Herafill packed into the tibial and femoral intramedullary canal during second stage of septic revision TKA is a reliable bone substitute, may reduce recurrence of infection and incorporates well with host bone. However, results after PJI treatment are less than optimal measured by KSSs as compared to patients who do not require revision.

Results of Total Cementless Hip Joint Arthroplasty with Taperloc Stem.

BACKGROUND: The aim of this paper is to present the results of hip joint arthroplasty with the use of the Taperloc stem. MATERIAL AND METHODS: The study group consisted of 117 patients (75 women and 42 men) who underwent 121 hip joint arthroplasties with Taperloc stems. Mean age of the patients at surgery was 53.8 years (range: 2475 years). Mean follow-up period was 159.5 months. RESULTS: Pre-operative Merle d'Aubigne-Postel scores (modified by Charnley) of the study group were poor in all patients. Mean post-operative improvement was 6.6 points. Excellent results were obtained in 86 cases, good in 19, fair in 9 and poor in 7 cases. Poor results were always associated with implant component loosening: 5 cases of acetabular cup loosening, 1 case of a loosened stem and 1 septic loosening of the entire endoprosthesis. In six cases (4.9%), patients developed heterotopic ossification. According to the Kaplan-Meier estimator, 10 years' survival probability was 94.21% for the whole endoprosthesis and 98.34% for the stem alone. CONCLUSIONS: 1. Our follow-up data covering a mean period of over 13 years showed that the use of the Ta-perloc stem substantially reduces hip pain and results in a good lasting clinical outcome. 2. With good surgical technique and in the absence of complications, the risk of aseptic loosening is minimal.

Evaluation of Outcomes of Total Knee Replacement with and without a Navigation System.

BACKGROUND: The aim of this study was to compare the results of TKA performed with the use of a navigation system vs. conventional knee arthroplasty and to evaluate the effectiveness of navigation system support in TKA. MATERIAL AND METHODS: We evaluated patients undergoing TKA for osteoarthritis in the years 2011-2013. Columbus prostheses were implanted in 84 knees. Group 1 included patients in whom TKA was performed with the use of the OrthoPilot Navigation System, and Group 2 was a control group of patientsundergoing conventional TKA. Group 1 ultimately comprised 30 patientsat a mean age of 71.8 years, while Group 2 consisted of 30 patients at a mean age of 73.5 years. Radiographic parameters were evaluated according to the mechanical axis of the leg. Clinical evaluation relied on the VAS and KSSscores. RESULTS: Mean operation time was 94 minutes in Group 1.It was shorter in Group 2, with a mean of 75 minutes. Postoperative VAS scores did not differ betweenthe groups. Significant improvement was noted between pre- and postoperative in KSS scores in both groups. The control group showed more valgus mechanical axis deviation than varus deviation. CONCLUSIONS: In experienced hands, navigated surgery time may be similar to that of conventional TKA and give superior results, both clinical and radiographic.