Preoperative Knee Society Score Research Articles

The Effect of Payer Type on Clinical Outcomes in Total Knee Arthroplasty

This was a retrospective cohort analysis of 112 patients undergoing primary total knee arthroplasty, wherein baseline demographics, resource utilization, and outcomes were compared by insurance type: Medicaid, Medicare, or private. At the time of surgery, Medicaid patients were younger (P<.0001) and had lower preoperative Knee Society Scores than Medicare and private patients (P=.0125). Medicaid postoperative scores were lower than those of private patients (P=.0223). The magnitude of benefit received by Medicaid patients was similar to Medicare and private patients. Medicaid patients had a higher number of cancelled (P=.01) and missed (P=.0022) appointments relative to Medicare and private patients. Medicaid patients also had shorter average follow-up periods compared to private patients (P=.0003). Access to care and socioeconomic factors may be responsible for these findings.

Effect of arthritis in other compartment after unicompartmental arthroplasty

The purpose of this study is to evaluate the outcome of robotic-assisted (MAKO Surgical Corp.) unicondylar replacement in the treatment for knee osteoarthritis after the initial surgical insult is worn off to evaluate the impact of residual patellofemoral and lateral osteoarthritis on the outcome of medial unicompartmental knee replacement. One hundred and thirty-four patients who underwent uncomplicated 144 robotic-assisted medial unicondylar replacements for knee arthritis were identified and studied. Original radiographs were used to classify severity of patellofemoral and lateral compartmental osteoarthritis in these patients. Severity of patellofemoral and lateral compartmental osteoarthritis was analyzed against Oxford and Knee Society scores and amount of ipsilateral residual knee symptoms at 6months postoperative period. Preoperative Oxford and Knee Society scores, other comorbidities and long-term disability were studied as confounding variables. We found significant improvement in symptoms and scores in spite of other compartment diseases. Poorer outcome was seen in association with comorbidities and long-term disability but not when radiographic signs of arthritis in the other compartments were present. Six patients required revision of which three had (lateral facet) patellofemoral disease in the original X-rays. In conclusion, there is a higher amount of postoperative retained symptoms, but similar outcome when there is radiographic disease in the other compartments. However, when symptoms are severe enough to necessitate revision, this is due to thelateral facet of patellofemoral compartment and not lateral compartment disease.

Tibial rotational osteotomy and distal tuberosity transfer for patella subluxation secondary to excessive external tibial torsion: surgical technique and clinical outcome

Recurrent patella subluxation may be secondary to excessive external tibial torsion. The purpose of this study is to evaluate the clinical and radiographic outcome of patients undergoing tibial derotation osteotomy and tibial tuberosity transfer for recurrent patella subluxation in association with excessive external tibial torsion. A combined tibial derotation osteotomy and tibial tuberosity transfer was performed in 15 knees (12 patients) with recurrent patella subluxation secondary to excessive external tibial torsion. Clinical evaluation was carried out using preoperative and post-operative Knee Society Score (KSS), Kujala Patellofemoral score, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire, the short form-12 (SF-12) and a visual analogue score (VAS) pain scale. The median follow-up period was 84 months (range 15-156) and median patient age was 34 years (range 19-57 years). The median preoperative external tibial torsion was 62° (range 55°-70°), with a median rotational correction of 36° (range 30°-45°) after surgery. Significant improvement (p < 0.05) was found in the KSS part I (37 ± 14 to 89 ± 11 points), KSS part II (25 ± 26 to 85 ± 14 points), Kujala score, the SF-12 outcome, WOMAC score and VAS score (8.8 ± 1.9 to 2.4 ± 1.5). Two patients had a nonunion of the tibial osteotomy site; one patient required bone grafting, while another patient required revision to total knee arthroplasty. Patients presenting with recurrent patella subluxation secondary to excessive external tibial torsion >45° who underwent tibial derotation osteotomy and tibial tuberosity transfer achieved a satisfactory outcome in terms of pain relief and improved function. A significant complication was seen in 2/15 patients. Case series, Level IV.

Preservation of subchondral sclerosis as the platform for tibial component support in total knee arthroplasty

Background In the present study, we hypothesize that preservation of adequate surface area of the subchondral sclerotic bone on the proximal tibial cut surface would provide a stronger foundation for tibial component support. This would minimize or eliminate the potential for component subsidence or loosening when minor degrees of misalignment are encountered, added to the potential advantage of avoiding complex reconstruction in osteoarthritic varus knees with excessive medial wear. The purpose of this study was to investigate the midterm outcome of total knee arthroplasty upon seating the tibial component partially on the medial sclerotic subchondral bone in varus osteoarthritic knees. Patients and methods Proximal tibial resection was kept to a minimum in 54 consecutive primary total knee arthroplasties. The remaining sclerotic surface area on the medial tibial plateau cut surface was freshened with a saw blade, and multiple anchorage holes were made for cement interdigitation. Patients were followed up for a mean period of 38.4 months both clinically and radiologically according to the knee society scoring system. Results At the last follow-up, the average clinical knee society score (KSS) was 88.4 (range from 72 to 94) compared with an average preoperative KSS of 32.5. The average knee function score at the last follow-up was 86.3 (range from 68 to 93) compared with the average preoperative functional score of 31.7. The coronal tibial component β angle was within ±3π of neutral alignment in 94% (51) of patients. The mean β angle was 89.6±2.8π, with a mean varus deviation of 0.4π from the neutral angle. At the latest follow-up, there was no was no evidence of component loosening or subsidence in any of the cases in this study. Conclusion In conclusion, the proposed surgical approach has proven beneficial to midterm durability and survival of the total knee implant on both clinical and radiographic basis. Avoidance of complex reconstruction is another potential advantage of adopting this technique in osteoarthritic varus knees with excessive medial wear. Further long-term follow-up studies are required to document the long-term durability.

Medial Unicompartmental Knee Arthroplasty in Patients Less Than 55Years Old: Minimum of TwoYears of Follow-Up

Eighty-five fixed bearing medial unicompartmental arthroplasties were performed in 42 men and 33 women with a mean age of 49 years (range, thirty-three to fifty-five years old) at the time of surgery. At a mean of 4.0 years (range two to twelve years), the mean pre-operative Knee Society score improved from 49 to 95.1 points (P<0.0001) and the mean UCLA activity score was 7.5 (range 5 to 9). Three knees underwent revision to a total knee arthroplasty; two for arthritic progression in the lateral compartment and one for pain. At the time of final follow-up, two knees (2.4%) demonstrated progressive Grade 4 arthritis of the patellofemoral compartment but were asymptomatic. There was no radiographic evidence of loosening, osteolysis, or premature polyethylene wear. Estimated survivorship was 96.5% at 10 years. UKA offered excellent early outcomes in this cohort of younger, active patients.

Effect of total knee arthroplasty on type II diabetes mellitus and hypertension: A prospective study

Context:Advanced osteoarthritis of knee joint if bilateral, severely restricts patient mobility. This acts as an aggravating factor for pre existing comorbid elements of metabolical syndrome (MS) like Type II diabetes mellitus and hypertension as patients are unable to carry out therapeutic walks. Successfully implanted total knee arthroplasty (TKA) increases physical activity and enables to carry out therapeutic walks thus may help in better control of type II diabetes mellitus and hypertension. The objective of this prospective study was to find whether TKA for osteoarthritis knee had any effect to improve blood glucose levels and reduce blood pressure.Materials and Methods:A prospective study was done in which patients operated for tricompartmental osteoarthritis of knee with associated comorbidities like Type II diabetes mellitus or hypertension during a period of 2008 and 2009 were studied. One hundred and twenty patients were enrolled (55 diabetics, 65 hypertensives) who met our inclusion criteria. Preoperative knee society score, lower extremity activity scale fasting blood glucose level and systolic and diastolic blood pressure were compared with one year followup values. The KSS and LEAS scores were analysed by the Wilcoxon signed ranked test, while the fasting blood glucose (FBG) levels and systolic and diastolic blood pressure levels were analysed by paired ‘t’ test.Results:The reduction of systolic blood pressure by 8 mmHg (t = 5.6, P value < 0.05) and diastolic blood pressure by 6 mmHg (t = 7.6, P value < 0.05) was recorded which was statistically significant. However, no statistically significant effect on fasting blood glucose levels was observed (t = -0.77, P value = 0.442). KSS improved in DM from preoperative 29 to 86 and LEAS improved from 6.7 to 11.3.Conclusions:Authors are of the opinion that successful total knee replacement results in increased physical activity and reduces blood pressure (systolic and diastolic) in hypertensives. However, the same is not seen in blood glucose level. Increased physical activity and reduced dependence on NSAIDS postoperatively, may be contributing in reduction of systolic and diastolic blood pressure. Further studies in this aspect are necessary.

Mid term results of LCS knee: The Indian experience

Background:The low contact stress rotating platform (LCS RP) knee (DePuy Orthopedics, Inc, Warsaw, Indiana), in use for last four decades in Western population, is reported to have a survival of more than 95% at 15 to 20 years. The reported Indian experience of this knee is limited to 5 years. Our aim was to report the clinical and radiological results of the LCS RP TKA design in the Indian population with a minimum followup of 10 years.Materials and Methods:Fifty-five LCS knees (45 patients) operated between February 1997 and October 2001 were evaluated retrospectively. LCS design was generally selected if the patient was young (≤65 years of age), active and had no severe deformity. There were 40 female (88.9%) and 5 male (11.1%) patients; 47 knees had osteoarthritis (85.5%) and 8 knees had rheumatoid arthritis (14.5%). Knee Society Scores (KSS) and outcome questionnaire were filled at followup and radiographs were analyzed using Knee Society radiographic evaluation and scoring system.Results:Of 45 patients (55 knees) enrolled, 37 patients (44 knees; 80%) were available for followup at 10 years. Average age was 59.6 years (range 40 to 77). Minimum followup was 10 years (average 12.3 years; range 10 to 15.3 years.). Three knees (6.8%) had been revised, one each for aseptic loosening, bearing dislocation and infection. Mean preoperative KSS of 33 improved to 91 postoperatively. Mean preoperative functional score of 45 improved to 76 postoperatively. Mean preoperative flexion of 113° (90°-140°) reduced to 102° (80°-135°) postoperatively. Erratic femoral rollback and tighter flexion gap to prevent spin out are the probable factors for decreased postoperative range of motion. Five (12%) patients could sit cross-legged and sit on the floor. Anterior knee pain was present in 4.6% (2/44 knees). The survival was 93.2% at 12.3 years. One patient (1.8%) had spin-out of the rotating bearing. No knee had osteolysis or progressive radiolucent lines on X-rays.Conclusion:LCS implant has given good survival (93.2% at 12.3 years) with low rates of spin-out and anterior knee pain and no incidence of osteolysis. Limited flexion post surgery (104°) with only 12% managing to sit cross legged on the floor is a drawback.

Predictors of functional outcome after revision total knee arthroplasty following aseptic failure

BackgroundThere are a limited number of studies related to quality of life and functional outcome after revision total knee arthroplasty (TKA). The present study aimed to identify predictors of functional outcome after revision TKA for aseptic failure. MethodsOne hundred seventy-five patients with mean age of 66.6years (range, 35–88) who underwent revision TKA for aseptic failure at our institute from 2003 to 2007 were identified. Short-form 36 (SF-36), Western Ontario and McMaster Osteoarthritis Index (WOMAC) and Knee Society Scores (KSS) collected preoperatively and at 2years follow up were evaluated. Univariate and multivariate analyses were performed to determine predictors of functional outcome in studied patients. ResultsBoth physical and mental dimensions of SF-36, pain, functional, and stiffness subscales of WOMAC and both functional and clinical scores of KSS improved significantly after revision TKA (p<0.001). In the multivariate analysis, male gender, a lower Charlson comorbidity index, and higher preoperative functional KSS were predictors of higher functional KSS at 2years after revision. Lower preoperative pain and higher clinical KSS were predictors of better outcome as measured by pain scale of WOMAC. Body mass index (BMI) and preoperative clinical KSS were significant predictors of function and stiffness as measured by WOMAC. ConclusionsBMI is a modifiable predictor of functional outcome after revision TKA. Moreover, patients with higher preoperative functional scores appear to have better postoperative function. Level of evidenceLevel II.

The aetiology of total knee arthroplasty failure influences the improvement in knee function

Some indications for revision total knee arthroplasty (TKA), e.g. arthrofibrosis, have been identified to yield inferior results. The aim of this study was to analyse the results of revision TKA according to aetiology of TKA failure. The results of 97 consecutive revision TKA in 97 patients stratified according to the aetiology of primary TKA failure (periprosthetic infection, aseptic loosening, instability and arthrofibrosis), were compared using the Knee Society Score (KSS). The effect of patient age, gender, BMI, American Society of Anesthesiologists (ASA) classification, interval to revision and the occurrence of complications on the outcome were also analysed. After a mean follow-up of 29 months, the KSS had significantly improved in all patient groups (p < 0.001). The analysis of variance among patient groups depicted no significant differences between preoperative KSS (p = 0.618) and postoperative KSS (p = 0.915), while the magnitude of pre- to postoperative improvement showed significant differences between the groups (p = 0.006). The aetiology of primary TKA failure had an independent influence on pre- to postoperative improvement (p = 0.014). Of the other factors analysed, only the ASA classification had an independent impact on postoperative KSS (p = 0.045). The aetiology of TKA failure has an effect on the improvement in knee function from revision TKA. As no difference was observed between patient groups postoperatively, similar clinical results can be expected independent of the aetiology of primary TKA failure.

No difference in ROM and knee function between mobile and floating platforms in TKA

The purpose of this study was to determine whether the floating platforms (FP) were superior to rotating platforms (RP) in computer-navigated total knee arthroplasty (TKA) comparing the range of motion (ROM) as well as clinical and subjective function of the knee. This retrospective non-randomized single-centre cohort study includes 255 patients with a primary implanted computer-navigated e.motion™ (Aesculap B. Braun) TKA system, implanted because of clinical and radiological verified gonarthrosis. In 129 patients, the FP platform was implanted, and in 126 patients, the RP platform. As statistical procedures for differences between inlay type RP/FP in ROM and Knee Society Score (KSS) after 3- and 24-month follow-up, an analysis of covariance (with risk factors gender, age, BMI, preoperative ROM and preoperative KSS) was performed. Although preoperative ROM and knee society function score (KSS part II) were significantly higher in the FP group before surgery, there was no significant difference between RP and FP in ROM and KSS at 3- and 24-month follow-up. The FP platform design did not have an advantage in ROM as well as in clinical and subjective knee function compared with the RP platform in computer-navigated TKA neither in early follow-up examinations at 3 months postoperatively nor at long-time follow-up at 24 months postoperatively.

Minimum 6-Year Follow-Up of Revision Total Knee Arthroplasty Without Patella Reimplantation

Management options for the polyethylene patellar button during a revision total knee arthroplasty (TKA) include retention, revision, or removal of the button without replacement (patelloplasty). Our purpose was to determine the midterm outcome of patients undergoing revision TKA with patelloplasty. We retrospectively reviewed a single surgeon's database for patients undergoing such surgery from May 2001 to June 2005 and identified 33 (34 knees). The 25 patients (26 knees) who had at least 6 years' follow-up formed our study group. We compared preoperative and final follow-up Knee Society Scores and radiographs. Mean Knee Society Scores had increased from 50 (range, 23-88) to 93 (range, 41-100), respectively. No patient required additional surgery. We conclude that, at midterm follow-up, patelloplasty appears to be a satisfactory option in the management of the patella in revision TKA.

Effect of gender differences in distal femoral geometry on the clinical outcomes of total knee arthroplasty

Objective To investigate the effect of gender differences in distal femoral geometry on the clinical outcomes of total knee arthroplasty (TKA). Methods From March 2003 to October 2006, 213 cases with 294 osteoarthritic knees who had underwent primary TKA were involved in the study. The study included 87 men (118 knees) and 126 women (176 knees) who had a mean age of 64.4 years. All the cases were assessed with the knee-rating system of Knee Society, the knee range of flexion (ROF), corrected posterior offset (PCO) and anterior condylar offset (ACO) based on sex. Results Each patient had a Minimum of 2 years follow-up. The preoperative Knee Society scores and ROF, the two-year postoperative changes of stability scores and walking ability had no differences between the two groups. While greater improvements of postoperative pain scores and stair-climbing ability were seen in male. Men had better intraoperative ROF than women had ones, but there were no gender differences with regard to the two-year postoperative improvement of ROF. Corrected PCO decreased more markedly in female than in male. Corrected ACO decreased equally in female and male. The difference in the posterior condylar offset after TKA was statistically correlated with the change in pain scores, stair climbing ability and intraoperative ROF, respectively. Conclusion Male had a better outcome than female did after TKA. Femoral components which designed in the light of Caucasian anatomic characteristics couldn't match the native anatomy of distal femurs of Chinese female. Sexual dimorphism in humans and anatomic variations in various ethnic groups should be seriously considered in total knee prosthesis design. Key words: Arthroplasty, replacement, knee; Gender identity; Prostheses and implants

Revision Total Knee Arthroplasty for Component Malrotation is Highly Beneficial: A Case Control Study

Component malrotation is a recognized cause of post total knee arthroplasty (TKA) pain. We reviewed 24 patients who had TKA revision due to component malrotation as the only objective abnormality. Mean combined component rotation was 6.8° excessive internal rotation, as documented by computed tomography. Twenty-four matched control patients had TKA revision due to aseptic loosening. Mean follow-up was 37 months. Preoperative Knee Society Score improved by 49 points at 6 months postoperatively for the malrotation patients and by 39 for the loosening patients. At last follow-up, Knee Society Score was 80 for the malrotation group and 75 for the loosening group. We recommend the use of computed tomography scans in evaluation of all patients with early painful TKAs and no objective evidence of infection. When component malrotation is demonstrated, early revision should be considered.

Functional Performance with a Single-radius Femoral Design Total Knee Arthroplasty

Better muscular recovery of the extensor mechanism after TKA is claimed by femoral designs based on a sagittal single radius. We aimed to compare postoperative knee performance through the Knee Society scores, flexor and extensor muscle function, stability, and gait of a series of patients receiving a posterior stabilized, cemented TKA, with a single-radius femoral design. We compared a series of patients treated with a single-radius femoral design TKA to a simultaneous series of patients receiving a multiradius femoral design. Both groups were similar in demographics and preoperative Knee Society scores. The clinical pathways were identical. Outcome assessment included Knee Society scores, isokinetic assessment, stabilometry, and gait cycle analysis. We observed higher functional Knee Society scores (86.6 +/- 1.89 versus 80.3 +/- 1.90), fewer physiotherapy sessions (19.9 +/- 4.65 versus 22.2 +/- 3.34), and less time with two crutches (3.5 +/- 1.2 versus 5.2 +/- 1.04 weeks) for patients receiving the single-radius design. Isokinetic evaluation showed decreased flexion peak torque (40.3 +/- 7.9 versus 48.7 +/- 9.6), increased extension peak torque (77.2 +/- 16.1 versus 69.1 +/- 14.4), and lower flexor/extensor ratio (0.5 +/- 0.08 versus 0.7 +/- 0.1) in patients with the single-radius design. Stabilometry showing less relative oscillation, and gait cycle indirectly confirmed better support in the limb with the single-radius design. The studied single-radius femoral design showed better functional short-term outcome and better extensor performance. Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Computer-Assisted Surgical Navigation Does Not Improve the Alignment and Orientation of the Components in Total Knee Arthroplasty

Whether total knee arthroplasty with use of computer-assisted surgical navigation can improve the limb and component alignment is a matter of debate. We hypothesized that total knee arthroplasty with use of computer-assisted surgical navigation is superior to conventional total knee arthroplasty with regard to the precision of implant positioning. Sequential simultaneous bilateral total knee arthroplasties were carried out in 160 patients (320 knees). One knee was replaced with use of a computer-assisted surgical navigation system, and the other was replaced conventionally without use of computer-assisted surgical navigation. The two methods were compared for accuracy of orientation and alignment of the components as determined by radiographs and computed tomography scans. The mean duration of follow-up was 3.4 years. The mean preoperative Knee Society score was 26 points, with an improvement to 92 points postoperatively, in the computer-assisted total knee arthroplasty group and 25 points, with an improvement to 93 points postoperatively, in the conventional total knee arthroplasty group. Preoperative and postoperative ranges of motion of the knees were similar in both groups. The operating and tourniquet times were significantly longer in the computer-assisted total knee arthroplasty group than in the conventional total knee arthroplasty group (p < 0.001). The groups were not significantly different with regard to the accuracy of component positioning and the number of outliers for the various radiographic parameters (p > 0.05). Our data demonstrate that total knee arthroplasty with use of computer-assisted surgical navigation did not result in more accurate implant positioning than that achieved in conventional total knee arthroplasty, as determined by both radiographs and computed tomography scans.

Influence of pre-operative variables on length of stay and outcome after unicompartmental knee replacement

The objective of this study was to determine whether pre-operative characteristics correlate with length of hospital stay or postoperative outcomes at 1 year following medial unicompartmental knee replacements (UKR). One hundred and eighty nine UKR patients and 223 knees were assessed pre-operatively and at one year post-operatively. The pre-operative variables of interest included: gender, age, body mass index (BMI), smoking history, uni- or bilateral procedures, pre-operative location, operative location, pre-operative Oxford Knee Score (OKS), clinical and functional American Knee Society Score (AKS) or Short Form-12 (SF-12). One year outcomes included the OKS, the clinical and functional AKS, SF-12, knee range of motion, and maximum and minimum visual analogue scale (VAS) pain scores, and length of hospital stay. Findings suggested that most pre-operative variables assessed correlated to maximum pain outcomes, and that the pre-operative clinical and functional AKS and SF-12 scores correlated with 1 year OKS and clinical AKS. Length of stay correlated with pre-operative OKS, SF-12, functional AKS, age and whether patients underwent uni- or bilateral procedures. Further study is recommended to compare these findings with alternative UKR populations.

Fulkerson Procedure for Chronic Patella Component Dislocation After Total Knee Arthroplasty

Chronic patella component dislocation after primary knee arthroplasty can be a challenging problem. The purpose of this case series was to review our results of a chronic patella dislocation after total knee arthroplasty treated with a Fulkerson procedure (anteromedialization of the tibial tubercle). Five patients with an average age of 68.8 years (range, 60-76 years) underwent a Fulkerson procedure to restore extensor mechanism alignment. The tibial tubercle osteotomy was secured with lag screws with an average medialization of approximately 1.5 cm. The average preoperative Knee Society score was 70.5 points that improved to 85 points postoperatively. The average knee flexion was 93° preoperatively that improved to 101° postoperatively. Adequate patellofemoral alignment was achieved in all patients along with union of the tibial tubercle osteotomy site. The Fulkerson procedure appears to be an excellent treatment option in patients with a chronically dislocated patella component after total knee arthroplasty.

Five- to 8-Year Results of the Uncemented Duracon Total Knee Arthroplasty System

We report prospective clinical and radiographic outcomes of a series of 219 hydroxyapatite-coated Duracon (Stryker Howmedica Osteonics Corporation, Kalamazoo, Mich) total knee arthroplasties with a follow-up of 5 to 8 years. Knee Society Score, Western Ontario and McMaster Universities Osteoarthritis index (WOMAC), and SF-12 Health Status Questionnaire were used. Analysis of fluoroscopic radiographs was performed with the American Knee Society Score. All living patients (186 knees) were followed up. Twenty-eight patients (30 knees) had died. The preoperative Knee Society Score of 43.8 increased to 77.1 and the preoperative Function score of 20.3 increased to 63.4. WOMAC scores showed marked improvement (pain, 250 preoperatively to 157; stiffness, 115 preoperatively to 56; and function, 910 preoperatively to 588). There was no radiographic evidence of loosening or migration. Gaps visible at the bone-implant interface healed over the first year. Three prostheses were revised, 2 for deep infection and 1 for tibial tray subsidence. A survivorship of 98.6% has been achieved at 8 years. This intermediate-term study with 100% follow-up at 8 years demonstrates excellent clinical and radiographic outcomes. It is our opinion that these are comparable to the gold standard cemented total knee arthroplasties and may have advantages over other uncoated cementless designs.

Bilateral staged total knee arthroplasty in obese patients

The purpose of this study was to compare the clinical and functional results and complications associated with staged bilateral total knee arthroplasty (TKA) performed 4-11 days apart during a single hospitalization in patients who were obese and patients who were not obese. We retrospectively evaluated 48 (96 knees) patients who were obese and divided into two groups based on their body mass indices (BMI). Morbidly obese patients (group A1, BMI > or = 40 kg/m2) consisted of 21 patients (42 knees), and obese patients (group A2, BMI > or = 30 kg/m2) consisted of 27 patients (54 knees). The control group (group B, BMI < 30 kg/m2) consisted of 20 non-obese patients (40 knees), who were undergoing staged bilateral procedure within the same time frame. All patients had cemented TKAs with use of posterior cruciate sparing prosthesis without patellar resurfacing. If medically stable after the first arthroplasty the patients then underwent the second arthroplasty 4-11 days later. The data on major complications and minor complications were evaluated. Although, there was no statistically significant difference in overall complication rates in any of the groups, the non-obese group had fewer wound complications than the other groups (P > 0.05). No significant differences in preoperative or postoperative Knee Society score, and functional score could be demonstrated between the three groups (P > 0.05). Both obese and nonobese patients showed improvements in pain and function from pre-surgery to a minimum 2 years follow-up. Results of bilateral staged TKAs in obese patients have low complication and high success rates and increased BMI has no negative effect on the early outcome. Bilateral staged TKA might be a good treatment alternative for the improvement of the patient's quality of life and functional and clinical outcomes.

A Mini-Midvastus Capsular Approach With Patellar Displacement Decreases the Prevalence of Patella Baja

Our aim in this study was to evaluate the prevalence of patella baja after total knee arthroplasty (TKA) using 2 different surgical techniques. Postoperative changes in patella height were measured on serial radiographs of 74 TKAs implanted using a mini-midvastus capsular approach without patella eversion (group 1) and 57 TKAs implanted using a standard medial parapatellar capsular approach with patella eversion (group 2). Preoperative and postoperative Knee Society scores, operative data, and complications were compared. With a cutoff level of 5% shortening, the prevalence was 12% in group 1 and 37% in group 2 ( P = .001). The presence of patella baja was related to reduced flexion and increased pain as early as 1 year after TKA.