Total Knee Arthroplasty Group Research Articles

Early Outcomes of Cemented versus Cementless Total Knee Arthroplasty

Introduction. Total knee arthroplasty (TKA) has been provento be very effective for long-term pain relief in the degenerativeknee. Few studies have investigated short-term clinicaland functional outcomes between the cemented and cementlessTKA. The specific aim of this study was to assess the potentialdifference of functional outcomes in the early postoperativeperiod between these two surgical options usingthe Knee Society Score (KSS) and range of motion (ROM).
 Methods. A total of 164 knees that had undergone TKA by a singlesurgeon at a single institution between 2007 and 2010 were reviewed.Three different TKA prosthetic designs (cruciate retaining(CR), posterior stabilized (PS) and cruciate substituting (CS))were included. Data collection included patient demographics,pre- and post-operative ROM, and pre- and post-operative KSSat each visit (1.5 months, 3 months, and 12 months). Two separateKSS scores were assigned: functional score and clinical score.
 Results. Sixty-seven knees underwent cemented TKA and 97knees underwent cementless TKA. No significant differencewas recognized in either age or body mass index for thesetwo TKA groups. The cementless group showed a significantearly ROM improvement after 1.5 months post-operative (p <0.05), while the cemented group showed ROM improvementonly after three months post-operative. No significant differencewas detected in terms of KSS between the cemented andcementless TKA groups at each measured time period. Bothgroups showed marked KSS improvement (cemented: 135%,cementless: 125%) after 1.5 months post-operative and theKSS seemed to be stabilized after three months post-operativefor both groups (cemented: p = 0.36; cementless: p = 0.07).
 Conclusions. There was a significant early ROM improvementfor the cementless TKA group compared to the cementedTKA group, but no statistical significant difference was notedin KSS in the early post-operative period when comparing cementedand cementless TKA groups. The findings provide evidencethat cementless TKA patients can undergo an identicalpost-operative protocol to cemented TKA, without concernsabout implant stability or function. KS J Med 2016;9(4):93-98.

An intraoperative load sensor did not improve the early postoperative results of posterior-stabilized TKA for osteoarthritis with varus deformities.

In the present study, the early results of sensor-assisted versus manually balanced posterior-stabilized total knee arthroplasty (TKA) for osteoarthritis with varus deformities were prospectively compared. Fifty patients undergoing sensor-assisted TKA (group S) and 50 patients receiving manually balanced TKA (group M) were prospectively compared. The groups did not differ in terms of demographics, preoperative clinical status, or severity of deformity. The knee and function scores (KS and FS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and range of motion (ROM) were evaluated clinically. The mechanical axes and positions of components were assessed radiographically. In sensor-assisted TKA, the medial and lateral compartment loads were compared based on the patellar positions of inversion and eversion. There was no between-group difference in the postoperative KS or FS (n.s., respectively). The average postoperative WOMAC score was 17.0 in group S and 18.0 in group M (n.s.). The ROM was 131.2° in group S and 130.8° in group M (n.s.). Neither the postoperative alignment of the mechanical axis nor the component positioning differed between the groups (n.s.). In sensor-assisted TKA, the difference between the medial and lateral compartment loads was less than 15lbs (6.8kg) in each knee. The lateral compartment load increased after patellar eversion (p < 0.001). There are concerns about the cost-benefit ratio of the intraoperative load sensor, despite its advantage of more precisely assessing ligament balance without patellar eversion, which resulted in a smaller lateral gap. A long-term follow-up study with a large cohort is required. II.

Robotic versus conventional primary total knee arthroplasty: clinical and radiological long-term results with a minimum follow-up of ten years

The aim of this study was (1) to compare the clinical and radiological outcomes of robotic and conventional total knee arthroplasty with a minimum follow-up of tenyears, (2) to evaluate the survival rate, (3) and to estimate the accuracy of the two techniques by analyzing the outliers of the total knee arthroplasty (TKA) patients. We evaluated 351 patients (390 knees), 155 patients undergoing robotic TKA, and 196 patients treated with conventional TKA with a mean follow-up of 11.0years. HSS, KSS, WOMAC, and SF-12 questionnaires were used for clinical evaluation. Mechanical alignment, implant radiological measurements, and outliers were analyzed for radiological results. Kaplan-Meier survival analysis was performed for survival rate. All clinical assessments showed excellent improvements in both groups (all p < 0.05), without any significant difference between the groups (p > 0.05). The conventional TKA group showed a significantly higher number of outliers compared with the robotic TKA group (0 < 0.05). The cumulative survival rate was 98.8% in the robotic TKA group and 98.5% in the conventional TKA group with excellent survival (p = 0.563). Our study showed excellent survival with both robotic and conventional TKA and similar clinical outcomes at long-term follow-up. And, in terms of radiological outcome, robotic TKA showed better accuracy and consistency with fewer outliers compared with conventional TKA. With longer follow-up and larger cohort, the accuracy and effectiveness of robotic TKA on implant survival rate can be elucidated in the future.

Compromised knee internal rotation in total knee arthroplasty patients during stair climbing.

Due to the significant role of rotational properties for normal knee function, this study aimed to investigate transverse plane kinematics and kinetics in total knee arthroplasty and unicondylar knee arthroplasty patients during activities of daily living compared to a healthy control group, including stair ascent and descent. The study participants consisted of a total knee arthroplasty group including posterior cruciate retaining and posterior stabilized designs as well as a unicondylar knee arthroplasty group and a healthy control group. Three-dimensional kinematics and kinetics were captured using a Vicon system and two Kistler force plates embedded in the floor and another two in a staircase. Inverse dynamics of the lower limbs was computed in Anybody™ Modeling System. Transverse plane joint angles and joint moments were analyzed utilizing the statistical non-parametric mapping approach, considering the entire curve shape for statistical analysis. The patients with total knee arthroplasty exhibited significantly reduced knee internal rotation of the operated knee compared to the control group and the patients’ unimpaired limb, especially during the stair climbing tasks. Both unicondylar and total knee arthroplasty patients were found to have similar reduced internal rotation motion time series in stair descent. In conclusion, potential kinematic and kinetic benefits of unicondylar knee arthroplasty over total knee arthroplasty could not be proven in the current study. Aside from the usually mentioned reasons inducing constrained knee internal rotation in total knee arthroplasty patients, future studies should investigate to what extent co-contraction may contribute to this functional impairment in patients after knee arthroplasty surgery.

Characteristics of Patients With Satisfactory Functional Gain Following Total Joint Arthroplasty in a Postacute Rehabilitation Setting.

Total joint arthroplasty (TJA) is an effective and successful treatment of osteoarthritis of the hip and knee as quantified by several measures, such as pain relief, improved walking, improved self-care, functions, and increased quality of life. Data are lacking as to the definition of a satisfactory functional gain in a postacute setting and identifying the characteristics of older patients with TJA who may achieve that gain. Our aim was to characterize patients who may achieve a satisfactory functional gain in a postacute rehabilitation setting following TJA. This was a retrospective study of 180 patients with TJA admitted during 2010-2013. The main outcome measures were the Functional Independence Measure (FIM), the Montebello Rehabilitation Factor Score (MRFS) on the motor FIM, and the Timed Get Up and Go Test. Satisfactory functional gain was defined as an mFIM MRFS score above median score. Comparisons of clinical and demographic characteristics between patients who achieved a satisfactory functional gain versus those who did not were performed by the Mann-Whitney U test and the χ test. The proportion of patients who achieved a satisfactory functional gain was similar in the total knee arthroplasty and total hip arthroplasty (THA) groups. The most significant characteristic of patients who achieved a satisfactory functional gain was their admission functional ability. Age negatively impacted the ability to achieve a satisfactory functional gain in patients with THA. Functional level on admission is the best predictive factor for a better rehabilitation outcome for patients with TJA. Age negatively affects functional gain in patients with THA.

Management of large bone defects around the knee using porous tantalum trabecular metal cones during complex primary and revision total knee arthroplasty

With the rising numbers and indications of primary as well as revision total knee arthroplasty (TKA), managing bone defects around the knee is an emerging challenge. This retrospective study evaluates the outcomes of Trabecular Metal (TM) cones used to address bone defects in 79 (20 primary and 59 revision) TKA cases. Range of motion and Knee Society Score improved significantly postoperatively, with better outcomes in the primary TKA group. Complete osteointegration was observed in all the cases. At an average follow-up of 6.6 years, major complications requiring re-operation were seen in 4 (5%) knees. TM cones are an effective option for treating severe bone defects during TKA with predictable osteointegration and good long-term clinical outcomes.

Incidence of deep vein thrombosis before and after total knee arthroplasty without pharmacologic prophylaxis: a 128-row multidetector CT indirect venography study

BackgroundWe sought to document the incidences of deep vein thrombosis (DVT) before and after total knee arthroplasty (TKA). In addition, we aimed to explor whether routine preoperative DVT evaluation was useful to establish DVT treatment strategies after TKA. Finally, we wanted to evaluate whether the incidences of DVT differed between patients undergoing unilateral and staged bilateral TKA within the same hospitalization period.MethodsThe retrospective study included 153 consecutive patients (253 knees) with osteoarthritis who underwent primary TKA. After surgery, mechanical compression devices (only) were used for DVT prophylaxis. DVT status before and after TKA was determined via 128-row, multidetector, computed tomography/indirect venography.ResultsOverall, the preoperative DVT incidence was 2.6% per patient and 1.6% per knee. All preoperative DVTs were distal in nature and asymptomatic. After TKA, newly developed thrombi were evident in various calf veins, without propagation of any pre-existing thrombi. Postoperatively, the overall incidences of DVT were 69.9% per patient and 58.5% per knee. The DVT incidences were 66% per patient and 69.8% per knee in the unilateral TKA group. In contrast, the incidences were 72% per patient and 55.5% per knee in the staged bilateral TKA group. There was one case of symptomatic distal (unilateral TKA; 0.65% per patient and 0.4% per knee) and proximal DVT (bilateral TKA; 0.65% per patient and 0.4% per knee), respectively.ConclusionsThe incidence of symptomatic DVT was low in Asian patients treated with mechanical compression devices alone, although substantial portion of patients had DVT after surgery. Routine preoperative DVT evaluation is probably not necessary; preoperative DVT was rare and of limited clinical relevance. Furthermore, staged bilateral TKA during a single period of hospitalization does not increase the incidence of DVT.

The impact of obesity on resource utilization among patients undergoing total joint arthroplasty.

The presence of obesity poses a challenge for clinical and administrative staff in the peri-operative setting. Evidence indicates that obesity may increase peri-operative complications. However, data on resource utilization in patients undergoing total knee and hip arthroplasty remain rare. Using national data, we sought to determine whether increasing levels of patient obesity is associated with greater resource utilization. We hypothesized that patient care in individuals with a body mass index (BMI) greater than 40 is associated with longer operative and anaesthetic times, longer hospital stays, and greater readmission rates. We utilized national data from the National Surgical Quality Improvement Project and identified patients who underwent primary total knee arthroplasty (TKA) and total hip arthroplasty (THA). Patients were divided into three groups according to their BMI (18.5 BMI < 30, 40 BMI < 45, and 45 BMI). The groups were compared regarding associated operating room utilization, length of stay, and readmission rates. Our study showed that TKA and THA patients with higher BMI required significantly longer operation-related times and had higher total length of hospital stay. Higher BMI patients also carried higher odds of readmissions within 30days in both TKA and THA groups. We conclude that BMI status needs to be considered for both medical and economic reasons by health care institutions and payers, in order to make prudent decisions in a world where health care expenses are rising rapidly alongside the increasing obesity epidemic, and resources are becoming increasingly scarce.

Short-term effectiveness of total knee arthroplasty assisted by three-dimensional printing osteotomy navigation template

To investigate the short-term effectiveness of total knee arthroplasty (TKA) assisted by three-dimensional (3D) printing osteotomy navigation template. A retrospective study was performed on 60 patients with osteoarthritis bewteen January 2016 and June 2017. Thirty cases underwent TKA assisted by 3D printing osteotomy navigation template (3D printing group) and 30 cases underwent the conventional TKA (conventional TKA group). There was no significant difference in gender, age, body mass index, surgical side, and disease duration between 2 groups ( P>0.05). The operation time, the pre- and post-operative hemoglobin values, the amount of drainage, the Hospital for Special Surgery (HSS) score and Knee Society Score (KSS) of knee joint before operation and at 3 months after operation were observed. And 6 freedom degrees of knee (the varus and valgus angle, the internal and external rotation angle, the antero-posterior displacement, the proximal-distal displacement, the flexion and extension angle, and the internal and external displacement) before operation and at 3 months after operation were recorded by Opti-Knee (the knee 3D motion analysis system). The values of 2 groups were compared with 30 healthy adults (<60 years). The operation time was shorter in 3D printing group than that in conventional TKA group ( t=5.833， P=0.000). The hemoglobin values at 1 and 3 days after operation were higher in 3D printing group than those in conventional TKA group ( P<0.05). The amount of drainage was less in 3D printing group than that in conventional TKA group ( t=5.468， P=0.000). All patients were followed up 6-9 months (mean, 7.3 months). There was no significant difference in pre- and post-operative HSS score and KSS clinical score between 2 groups ( P>0.05). There was no significant difference in preoperative KSS function score between 2 groups ( P>0.05), but the KSS function score of 3D printing group at 3 months after operation was higher than that of conventional TKA group ( P<0.05). Before operation, the varus and valgus angle, the internal and external rotation angle, the antero-posterior displacement, the proximal-distal displacement of 3D printing group and conventional TKA group were larger than that of the healthy adults ( P<0.05); there was no significant difference in the flexion and extension angle and the internal and external displacement between 2 groups and healthy adults ( P>0.05). At 3 months after operation, compared with healthy adults, the varus and valgus angle of conventional TKA group was increased, the flexion and extension angle of conventional TKA group was decreased ( P<0.05); the proximal-distal displacement and the internal and external displacement of 2 groups were decreased ( P<0.05); there was no significant difference in other freedom degrees between groups ( P>0.05). No sign of prosthesis loosening was observed by X-ray examination. Compared with the traditional TKA, TKA assisted by the 3D printing osteotomy navigation template had such advantages as shorter operation time, less postoperative blood loss, and well postoperative recovery.

Improvement in Health-related Quality of Life After Total Ankle Arthroplasty Compares Well to Other Successful Orthopaedic and Non-orthopaedic Procedures

Category: Ankle Arthritis Introduction/Purpose: End-Stage arthritis is one of the leading causes of chronic disability in the United States. Improvement in Health-Related Quality of Life(HRQOL) after total ankle arthroplasty(TAA) has been demonstrated in the literature. This improvement has not been compared to that of other common Orthopaedic and non-Orthopaedic procedures including Anterior Cervical Discectomy and Fusion(ACDF), Total Knee Arthroplasty(TKA), Coronary Artery Bypass Grafting(CABG), and Orthotopic Liver Transplant(OLT). Although TAA is noted to be effective in eliminating symptoms in end-stage arthritis, it is difficult to gauge the impact of TAA relative to other meaningful procedures that have been shown to have great impact on HRQOL improvement. The purpose of this study was to compare changes in HRQOL between TAA and other common procedures with large impacts on this outcomes measure. Methods: Five hundred consecutive patients with minimum of two-years follow-up after TAA were prospectively evaluated with the Short Form-36(SF-36) outcome instrument preoperatively, at six months, one year and two years post-operatively. An exhaustive literature review was conducted identifying studies with comparatively sample sizes comparing preoperative and postoperative SF-36 scores after ACDF, TKA, CABG, and OLT. The SF-36 Physical and Mental component scores were included in each cohort and compared for magnitude of improvement and significant differences between them. Results: Patients in all cohorts had preoperative SF-36 mental and physical function scores significantly lower than the general population scores. The preoperative physical function scores were lowest in the TKA group (average 31.1 +/-9.7) followed by TAA group (average 40.6 +/-16.3), ACDF group (average 41.5 +/-21.6), OLT group (average 51.9 +/-23.6) and CABG groups (57.8 +/-21.3), respectively. Improvement after surgery was greatest in the ACDF group (Mental +31.5, Physical +22.9), followed by the TAA group (Mental +13.9, Physical +26.8), TKA group (Mental +14.3, Physical +22.4), CABG group (Mental +7.6, Physical +15.4) and OLT group (Mental -4.47, Physical +9.8), respectively. The greatest improvement in physical function score occurred in the TAA group (see attached table). Conclusion: The mental and physical disability associated with end-stage ankle arthritis is as severe as that associated with many other Orthopaedic and non-Orthopaedic conditions. The improvement in HRQOL after TAA is greater than that obtained after TKA, CABG, and OLT but not as great as the improvement seen after ACDF; however, the improvement in physical function score was greatest in the TAA cohort. The HRQOL benefits of TAA are comparable to the benefits achieved after several other relatively common and successful surgical procedures.

Navigated versus conventional total knee arthroplasty: A prospective study at three years follow-up

ObjectiveComputer-assisted surgery application in total knee arthroplasty (TKA) has shown more accurate implant alignment compared with conventional instrumentation and is associated with more homogeneous alignment results. Although longer implant survival and superior clinical outcomes should be expected from navigated TKA, currently available evidence does not support this hypothesis. The aim of this study was to compare navigated TKA with conventional TKA regarding clinical and radiological outcomes after a 3-year follow-up under the hypothesis that navigated TKA would provide better outcomes than conventional TKA. Material and methodIn a prospective multicentre study, 119 patients underwent navigated TKA and 80 patients received conventional instrumentation. Patients were evaluated at the baseline and at postoperative months 3, 12, 24, and 36. Analysis included the American Knee Society Score (KSS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Short Form-12 (SF12) Health Survey, and radiographic assessment. ResultsAll clinical scores improved significantly for all patients during the follow-up but were significantly better in the navigation group.The percentage of patients showing a mechanical axis between 3° of varus and 3° of valgus was significantly higher in the ATR group (93%) than in the conventional TKA group (71%) (p<.01). ConclusionsThe use of computer-assisted surgery in TKA provides more accurate mechanical alignment and superior short-term functional outcomes compared to conventional TKA.

Alignment in total knee arthroplasty — A comparison of patient-specific implants with the conventional technique

BackgroundIncorrect positioning and malalignment of total knee arthroplasty (TKA) components can result in implant loosening. Restoration of neutral alignment of the leg is an important factor affecting the long-term results of TKA. The aim of our retrospective study was to compare mechanical axis in patients with conventional and patient-specific TKAs. Methods232 patients who underwent TKA between January 2013 and December 2014 were included to compare postoperative mechanical axis. 125 patients received a patient-specific TKA (iTotal CR®, Conformis) and 107 a conventional TKA (Triathlon®, Stryker). Standardized pre- and postoperative long-leg standing radiographs were retrospectively evaluated to compare the two patient cohorts. Results113 (90%) radiographs of patient-specific TKA and 88 (82%) of conventional TKA were available for comparison. The preoperative deviation from neutral limb axis was 9.0° (0.1–27.3°) in the patient-specific TKA cohort and 8.2° (0.2–18.2°) in the conventional TKA group. Postoperatively the patient-specific TKA group showed 3.2° (0.1–8.4°) and the conventional TKA cohort 2.3° (0.1–12.5°) deviation. However, the rate of ±3° outliers from neutral limb axis was 16% in the patient-specific TKA cohort and 26% in the conventional TKA group. ConclusionsPatient-specific TKA demonstrated fewer outliers from neutral leg alignment compared to conventional technique. Potential benefits in the long-term outcome and functional improvement require further investigation.

Incidence of symptomatic venous thromboembolism in 2372 knee and hip replacement patients after discharge: data from a thromboprophylaxis registry in Montreal, Canada.

BackgroundLow-molecular-weight heparin (LMWH) is a recommended anticoagulant for thromboprophylaxis after major orthopedic surgery. Dabigatran etexilate is an oral anticoagulant recognized as noninferior to LMWH. We aimed to assess the incidence of symptomatic venous thromboembolic events (VTEs) after discharge in patients who underwent joint replacement, using a hospital registry.Patients and methodsPatients who underwent total knee and hip arthroplasty between September 2011 and March 2015 were selected. Subcutaneous enoxaparin (30 mg twice daily) was given during hospitalization. At discharge, patients received either enoxaparin 30 mg twice daily/40 mg once daily or dabigatran 220 mg/150 mg once daily. Patients were seen or called at 2, 6, and 12 weeks after surgery. Outcomes were the number of VTEs, including deep venous thrombosis, pulmonary embolism, and the number of major/minor bleeding events after discharge.ResultsAfter discharge, 1468 patients were prescribed enoxaparin and 904 dabigatran (1396 total knee arthroplasty and 976 total hip arthroplasty patients). Mean age was 66±10 years, and 60% were female. The cumulative incidence of VTEs during the 12-week follow-up was 0.7%. One patient sustained a VTE during the switch window. Seven patients sustained a pulmonary embolism (0.3%). There was no statistical difference between the total knee arthroplasty and total hip arthroplasty groups. The incidence of major and minor bleeding events during follow-up was 0.3% and 30.3%, respectively. These events had a higher incidence in the dabigatran group compared to the enoxaparin group after discharge (p<0.05), but not between knee and hip replacement groups for major bleeding events.ConclusionA pharmaceutical prophylaxis protocol using LMWH and dabigatran during the post-discharge period resulted in low incidences of VTE and equivalence between treatments. However, the increased number of major and minor bleeding events in patients taking dabigatran is of concern regarding the safety and needs to be evaluated using analyses adjusted for risk factors.

Knee Arthroplasty Patients Predicted Versus Actual Recovery: What Are Their Expectations About Time of Recovery After Surgery and How Long Before They Can Do the Tasks They Want to Do?

Objectives(1) To determine evidence-based guidance for the length of time to return to specific valued functional and leisure activities after knee arthroplasty (KA). (2) To determine what patients feel are the most important functional or leisure activities to recover after KA. (3) To collect information about patients’ expectations and compare them to the actual time it takes to return. DesignProspective longitudinal cohort observational survey. SettingSpecialist orthopedic hospital. ParticipantsPatients (N=99) with osteoarthritis or rheumatoid arthritis (mean=69.9y [range 44-88]) listed for total knee arthroplasty (TKA) or unicompartmental knee arthroplasty. InterventionsNot applicable. Main Outcome MeasureValued activities list (VAL) used to select activities patients expect to return to and report the actual time taken to return. ResultsParticipants in unicompartmental knee arthroplasty group returned to the 6 most popular valued activities (walking >1km, stair climbing, housework, driving, gardening, and kneeling) 8%-33% more quickly than TKA group, and they were satisfied with performing these activities sooner on average (4%-18%) than the TKA group. The percentage of participants satisfied at 12 months postsurgery ranged from 96% returning to housework to 36% returning to kneeling. The Wilcoxon signed-rank test was used to compare the expected time and the actual time to return: Housework (Z=−5.631, P<.05, effect size=0.64) and swimming (Z=−3.209, P<.05, effect size=0.59) were quicker than expected, and walking >1 km (Z=−2.324, P<.05, effect size=0.27) was slower than expected. ConclusionsA more tailored and personalized approach with consideration of prior level of activity and comorbidities must be taken into account and adequately discussed to help bridge the gap between the expected and actual recovery time.

Arthroscopic revision surgery in the arthrofibrotic knee: who benefits?

Aims and Objectives: Arthrofibrotic stiffness of the knee joint has been recognized as a highly debilitating complication after complex knee reconstruction. The clinical impact of arthroscopic revision surgery was evaluated for patients with knee arthrofibrosis following total knee arthroplasty (TKA) and after joint preserving procedures. Hypothesis: Arthroscopic revision surgery is associated with functional benefits in both groups. Materials and Methods: We retrospectively reviewed a consecutive series of adult patients (#CHR: greaterlike#18 years) at a single institution who underwent arthroscopic revision for knee stiffness. Minimum follow-up: 24 months. The analysis included demographic, surgical and histological data. The following outcome parameters were evaluated: pain (Visual Analog Scale, VAS); objective score systems (Oxford Knee Score) and patient activity (Tegner Activity Scale (TAS), Univ. of California Activity Scale (UCLA)). Furthermore, range of motion (ROM) was compared pre-, intra- and postoperatively. Finally, we compared body mass index (BMI) and quality of life (EQ-5D) changes. Results: We identified a total of 57 patients who underwent arthroscopic adhesiolysis for knee arthrofibrosis: 45 after TKA (Group 1) and 12 patients with ligament reconstruction (Group 2). The patient cohort included thirty (43.5%) males and thirty-six (56.5%) females. Mean age was 69 (SD 10.6) years in the TKA group and 41 (SD 12.7) years in group 2 (p=0.01). Mean length of stay (LOS) was 4.6 days in Group 1 and 2.8 days in Group 2. Pain levels (VAS) were reduced significantly in both groups (p=0.004); from 7.5 to 4.8 in Group 1 and from 7.8 to 2.9 (Group 2). In terms of sports activity, 26 patients (37.7%) reported an improved sports activity (UCLA score). The TAS improved from 2.58 to 4.08 in Group 2. The Oxford Knee Score improved from 23.5 to 27.2 in Group 1 and from 16.5 to 36.3 in Group 2. No reduction in BMI was observed. However, quality of life (EQ-5D) improved from 47.6 to 51.9 Group 1; and from 52.9 to 71.7 in Group 2. Conclusion: Arthroscopic revision of the stiff knee may offer clinical benefits in terms of significant pain reduction, an improved level of activity and quality of life in stiffness following both TKA and joint preserving surgical reconstruction.

Artroplastia total de rodilla navegada versus convencional; estudio prospectivo a 3 años de seguimiento

ObjectiveComputer-assisted surgery application in total knee arthroplasty (TKA) has shown more accurate implant alignment compared with conventional instrumentation and is associated with more homogeneous alignment results. Although longer implant survival and superior clinical outcomes should be expected from navigated TKA, currently available evidence does not support this hypothesis. The aim of this study was to compare navigated TKA with conventional TKA regarding clinical and radiological outcomes after a 3-year follow-up under the hypothesis that navigated TKA would provide better outcomes than conventional TKA. Material and methodIn a prospective multicentre study, 119 patients underwent navigated TKA and 80 patients received conventional instrumentation. Patients were evaluated at the baseline and at postoperative months 3, 12, 24, and 36. Analysis included the American Knee Society Score (KSS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Short Form-12 (SF12) Health Survey, and radiographic assessment. ResultsAll clinical scores improved significantly for all patients during the follow-up but were significantly better in the navigation group.The percentage of patients showing a mechanical axis between 3° of varus and 3° of valgus was significantly higher in the ATR group (93%) than in the conventional TKA group (71%) (P<.01). ConclusionsThe use of computer-assisted surgery in TKA provides more accurate mechanical alignment and superior short-term functional outcomes compared to conventional TKA.

Subchondral stem cell therapy versus contralateral total knee arthroplasty for osteoarthritis following secondary osteonecrosis of the knee.

Total knee arthroplasty (TKA) implanted in patients with secondary osteonecrosis (ON) related to corticosteroids have relatively poor outcome (20% revision rate) at a mean follow-up of only eightyears. With the hypothesis that subchondral bone marrow injection might improve knees in these patients, we evaluated 30 patients who had bilateral knee osteoarthritis with severe joint space narrowing and received TKA in one knee and subchondral bone marrow concentrate injection in the contralateral knee. A prospective randomized controlled clinical trial was carried out in 60 knees of 30 patients (mean age 28years, 18-41) who presented bilateral osteoarthritis secondary to knee ON related to corticosteroids in relation with different severe medical conditions. During the same anesthesia, one knee received TKA; for the other knee, a bone marrow graft containing an average of 6500 MSCs/mL (counted as CFU-F, range 3420 to 9830) was delivered to the subchondral bone of the femur and tibia. The length of anesthesia related to each procedure (bone marrow aspiration and subchondral injection of concentrated bone marrow versus total knee arthroplasty) was measured. Peri-operative outcomes, morbidity, complications, and safety of the two procedures were compared. Subsequent admissions for revision surgery were identified. At the most recent follow-up (average of 12years, range 8 to 16years), clinical outcomes of the patient (Knee Society score) were obtained along with radiological imaging outcomes (MRIs for knees with subchondral bone marrow injection). Anesthesia related to the TKA side was longer than for the cell therapy group. Medical and surgical complications were more frequent after TKA. A higher number of thrombophlebitis was observed on the side with TKA (15%) versus none on the side with cell therapy (0%). At the most recent follow-up (average of 12years, range 8 to 16years), six (out of 30) TKA knees needed subsequent surgery versus only one with cell therapy. The Knee Score had improved and remained similar in the TKA and cell therapy groups (respectively 80.3 points ± 11 versus 78.3 ± 23); 21 patients preferred the knee with cell therapy and 9 preferred the knee with TKA. Knees with cell therapy had improvement on cartilage and bone marrow lesions observed at the site of bone marrow subchondral injection. Subchondral autologous bone marrow concentrate was an effective procedure for treating young patients with knee osteoarthritis following secondary ON of the knee related to corticosteroids with a lower complication rate and a quicker recovery as compared with TKA.

Effects of Femoral Lateral Bowing on Coronal Alignment and Component Position after Total Knee Arthroplasty: A Comparison of Conventional and Navigation-Assisted Surgery.

PurposeTo evaluate the effects of femoral lateral bowing on coronal alignment after total knee arthroplasty (TKA) and examine whether the use of navigation helps obtain better postoperative coronal alignment and component position.Materials and MethodsRadiological results and outlier rates were compared between the conventional TKA group and the navigation-assisted TKA group, and factors associated with postoperative alignment were evaluated. For clinical assessment, patient-reported outcomes were used.ResultsA total of 297 knees were retrospectively reviewed. Among the patients with femoral lateral bowing, a significant difference was observed between the conventional TKA group (n=72) and the navigation-assisted TKA group (n=96) in postoperative mechanical femorotibial angle (mFTA, 1.6° vs. 0.8°; p=0.005) and femoral component alignment angle (89.0° vs 90.0°; p=0.017). Preoperative mFTA (p<0.001), femoral bowing angle (p<0.001), and mechanical lateral distal femoral angle (p=0.032) had effects on postoperative mFTA in the conventional TKA group. In the navigation-assisted TKA group, only preoperative mFTA (p<0.001) had effects on postoperative mFTA.ConclusionsDespite the individualized determination of the valgus correction angle through preoperative planning, in the cases with severe lateral bowing, the outlier rate was higher in the conventional TKA group than in the navigation-assisted TKA group. However, there was no significant difference in the clinical results between the two groups in the short-term follow-up.

Unexplained pain following total knee arthroplasty: Is rotational malalignment the problem?

BackgroundMalrotation of tibial and femoral components is a potential source of pain following total knee arthroplasty (TKA). This study aimed to 1) compare component rotation in TKA patients with unexplained pain versus a control group with well-functioning TKAs and 2) investigate the relationship between TKA component rotation and pain. MethodsSeventy one patients with unexplained pain after primary TKA were compared to a control cohort of 41 well functioning TKA patients. Both groups underwent post-operative computed tomography (CT) scans to assess component rotation. Findings were compared between the painful and control TKA groups. ResultsWe found no difference in femoral component rotation between the painful and control groups (mean 0.6° vs 1.0° external rotation (ER), p=0.4), and no difference in tibial component rotation (mean 11.2° vs 9.5° internal rotation (IR), p=0.3). Also, there was no difference in combined mal-rotation (tibial+femoral rotation) between the groups (mean 10.5° vs 8.5°IR, p=0.25). Fifty-nine percent of patients in the painful group had tibial component rotation >9°IR vs 49% in the control group. ConclusionIn the largest study yet on component rotation after TKA, we found no difference in the incidence of tibial, femoral, or combined component mal-rotation in painful versus well-functioning TKAs. Tibial component IR relative to the junction of the medial to middle thirds of the tibial tubercle appears to be common in patients with well-functioning TKAs. The significance of slight tibial IR should be interpreted with caution when evaluating the painful TKA.Level III retrospective case–control study.

Quality of Recovery, Postdischarge Hospital Utilization, and 2-Year Functional Outcomes After an Outpatient Total Knee Arthroplasty Program

BackgroundOutpatient total knee arthroplasty (TKA) has been made possible with advances in perioperative care and standardized clinical inpatient pathways. While many studies report on benefits of outpatient programs, none explore patient-reported outcome measures. As such, our goals were to compare the short-term quality of recovery; highlight postdischarge hospital resources utilization; and report on 2-year functional outcomes scores. MethodsThis was a prospective comparative cohort study of 43 inpatients (43 TKAs) and 43 outpatients (43 TKAs) operated on by a single surgeon between September 28, 2010 and May 5, 2015. All patients were given a diary to complete at 1, 3, 7, 14, and 28 days postoperatively; we collected 90-day complications, readmissions, and emergency department visits; Knee Injury and Osteoarthritis Outcome Score and Western Ontario and McMaster Universities Osteoarthritis Index scores were completed preoperatively and 2 years postoperatively. SPSS (IBM, version 22.0) was used for all statistical analyses. ResultsQuality of recovery (QoR-9) was similar in the outpatient TKA group compared with the inpatient group. No statistically significant differences were observed for Knee Injury and Osteoarthritis Outcome Score and Western Ontario and McMaster Universities Osteoarthritis Index subscores (P > .05). There was 1 readmission in both outpatient and inpatient groups. Six inpatients and 8 outpatients returned to the emergency department for any reason within 90 days, with no statistical significance observed between the 2 groups (P = .771). ConclusionOutpatient TKA in selected patients produced similar short-term and 2-year patient-reported outcome measures and a comparable 90-day postdischarge hospital resource utilization when compared to an inpatient cohort, supporting further investigation into outpatient TKA.