Progression Of Tibiofemoral Osteoarthritis Research Articles

Long-Term clinical results of patellofemoral arthroplasty for isolated patellofemoral osteoarthritis.

The aim of this study was to explore the clinical outcomes and long-term survival of patellofemoral arthroplasty in treatment of isolated patellofemoral osteoarthritis. We retrospectively studied a total of 46 type Y-L-Q PFAs that were designed at our institution in 38 patients. Implant survivorship was analyzed with a follow-up of 18.9-29.6years. Knee Society Score (KSS), Oxford Knee Score (OKS), and University of California Los Angeles activity scale (UCLA) were used to assess functional outcomes. The implant survivorship was 83.6% at 15years, 76.8% at 20 years, and 59.4% at 25years 14 PFAs in 12 patients were revised into total knee arthroplasty at 16.0 ± 6.7years; 13 for progression of tibiofemoral osteoarthritis and one for polyethylene wear. The mean Knee Society Score objective scores and functional scores were 73.0 ± 17.5 (range, 49-95) and 56.4 ± 28.9 (range, 5-90), respectively. The mean Oxford Knee Score was 25.8 ± 11.5 (range, 8-44). Type Y-L-Q patellofemoral arthroplasty can be an effective method for treating isolated patellofemoral osteoarthritis with satisfactory survival.

Patellofemoral arthroplasty in combination with high tibial osteotomy can achieve good outcome for patients with medial-patellofemoral osteoarthritis.

BackgroundThe purpose of our study is to report on the clinical outcomes of patients who undergoing patellofemoral arthroplasty (PFA) in combination with a high tibial osteotomy (HTO). Due to this procedure's conservative and kinematics-preserving characteristics, we hypothesized that PFA in combination with HTO would result in good clinical outcomes in patients with medial and patellofemoral compartment osteoarthritis (MPFOA).MethodsPatients who underwent PFA in combination with HTO for MPFOA from January 2018 to April 2020 were included in the study. Clinical outcomes were analyzed by comparing the Knee Society Score, Oxford Knee Score, Range of Motion, and Forgotten Joint Score before and after the procedure. Radiological evaluations were also performed to assess the tibiofemoral osteoarthritis progression and implant loosening. For all tests, the value of p < 0.05 was considered statistically significant.ResultsA total of nine consecutive patients who underwent PFA in combination with HTO were included. Two were males, seven were females. The average follow-up period was 2.6 ± 0.4 years. Clinical outcomes showed a significant improvement in the Knee Society Score (clinical score: 90.3 ± 8.5 and function score: 90.8 ± 7.8), Oxford Knee Score (43.6 ± 3.6), Forgotten Joint Score (71.2 ± 10.2), and knee Range of Motion (130.4 ± 8.1°) at the final follow-up. Additionally, hip–knee–ankle angle significantly decreased from −9.3 ± 2.1° preoperatively to 2.2 ± 1.2° at the final follow-up (p < 0.05). There were no complications for any patient during the follow-up time.ConclusionThis study shows that patients who underwent PFA in combination with HTO for the treatment of MPFOA achieved good clinical and radiological outcomes. This combined surgery could be an effective alternative to treat MPFOA in well-selected patients.

Association of Mucoid Degeneration of the ACL with Medial Tibiofemoral Osteoarthritis Progression at MR Imaging

Abstract Background Using MRI, ACL mucoid degeneration is defined as a thickened ACL with increased signal intensity on all MR pulse sequences, with discrete fibers easily distinguished on fatsaturated T2-weighted or fat-saturated proton-density (PD)-weighted images but poorly differentiated on T1-weighted or non-fat-saturated PD-weighted images. Objective To assess the prevalence of ACL mucoid degeneration in a population of patients referred for routine knee MRI, and its association with age and structural joint damage. Patients and Methods Our study is a retrospective study conducted at the radiology department of Ain Shams University hospitals and Ain Shams University Specialized Hospital including 81 cases of knees with ACL mucoid degeneration by MRI and no sex predilection. Cases and controls were scored with respect to independent articular features: cartilage signal and morphology, subarticular bone marrow abnormality, subarticular cysts, subarticular bone attrition, marginal osteophytes and medial meniscal integrity. Results Patients with ACL mucoid degeneration were older than patients with a normal ACL, without statistically significant sex difference. Knees with ACL mucoid degeneration had statistically significant medial meniscal injuries and cartilage damage involving the central and posterior MTFC compared to control knees with a normal ACL frequency matched for age, sex and MR field strength. Conclusion Our study proved that there is a strong association between ACL mucoid degeneration and cartilage damage in MTFC.

The current place of patellofemoral arthroplasty in the treatment of isolated patellofemoral osteoarthritis

Patellofemoral(PF) osteoarthritis (OA) is a somewhat predominant illness, affecting up to 24% of women and 11% of men over the age of 55 years who suffer from symptomatic knee OA. The purposes of this narrative overview are to summarize the present situation of patellofemoral arthroplasty (PFA)in the treatment of solitary PF-OA, and to give an account of the clinical results of PFAfor the management of solitary PFdegenerative OA of the knee. A Cochrane Library and PubMed (MEDLINE) examination related to the position of PFA in PF-OA was carried out. A number of publications have encountered that PFA is an efficacious treatment for solitaryPF-OA. Additionally, a systematic review described fairly good results of PFA survivorship and functional outcomes at short- and mid-run follow-up in the setting of solitaryPF-OA. Success of PFA depends on accurate patient selection rather than prosthetic failure or wear. In many reports, the main cause of PFA failure is advancement of tibiofemoral OA. In contemporary times, encouraging results have been accomplished by the association of PFA and unicompartmental knee arthroplasty (UKA). In conclusion, patients with solitaryPF-OA with severe anterior knee pain may be candidates forPFA. The success of the surgical procedure and the long-run survivorship of PFA are related to a good surgical technique and observation to meticulous indications and contraindications in patient selection. Newer prostheses have also played a part to ameliorated outcomes. PFA is an alternative for younger patients with solitaryPF-OA.

Patellofemoral morphology measurements and their associations with tibiofemoral osteoarthritis progression: exploratory analysis on the osteoarthritis initiative

Patellofemoral morphology measurements and their associations with tibiofemoral osteoarthritis progression: exploratory analysis on the osteoarthritis initiative

High patient satisfaction with significant improvement in knee function and pain relief after mid-term follow-up in patients with isolated patellofemoral inlay arthroplasty.

To prospectively evaluate the clinical and radiographic outcomes and survivorship at 2 and 5years after isolated contemporary patellofemoral inlay arthroplasty. Thirty-four patients were prospectively enrolled in the study and were evaluated preoperatively and at 2 and 5years postoperatively. Clinical outcomes included the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score and the visual analogue scale (VAS) for pain. Kellgren-Lawrence grading was used to assess the progression of tibiofemoral osteoarthritis and the Caton-Deschamps Index to determine patellar height. A Kaplan-Meier survival analysis was used to investigate the implant survivorship. Preoperative patient characteristics were compared among failures and success to determine potential risk factors and patient satisfaction was rated postoperatively. Five of the 34 patients were lost to follow-up resulting in a final follow-up rate of 86%. The total WOMAC subscores of pain and function and the VAS Pain improved significantly at 2- and 5-years, with no significant difference between the two time points. The WOMAC stiffness subscale reached significant improvement at 2-year follow-up alone. No significant progressions of tibiofemoral arthritis or changes in patellar height were observed. A total of six patients (17.1%) failed leaving a survival rate of 91% after 2 years and 83% after 5 years. The main cause for postoperative failure was persistent knee pain; however, no significant preoperative risk factor in patient characteristics could be identified. Patellofemoral inlay arthroplasty shows high patient satisfaction with significant improvement in knee function and pain relief after mid-term follow-up with no radiographic progression of tibiofemoral OA. Prospective case series, Level III.

Association of Mucoid Degeneration of the Anterior Cruciate Ligament at MR Imaging with Medial Tibiofemoral Osteoarthritis Progression at Radiography: Data from the Osteoarthritis Initiative.

Purpose To determine whether anterior cruciate ligament (ACL) mucoid degeneration in participants with or at risk for osteoarthritis is associated with longitudinal risk of radiographic progression of medial tibiofemoral compartment joint space loss (JSL). Materials and Methods Baseline demographic, clinical, radiographic, and Magnetic Resonance (MR) Imaging Osteoarthritis Knee Score (MOAKS) data were evaluated in 600 participants from the Osteoarthritis Initiative database. Two blinded musculoskeletal radiologists independently evaluated baseline MR images for ACL mucoid degeneration. Multiple logistic regression was used to investigate the association between ACL mucoid degeneration at MR imaging and JSL progression at radiography, defined as a minimum joint space width decrease greater than 0.7 mm (48 months; cutoff according to mean and standard deviation of 1-year minimum joint space width changes in 90 knees of reference group). Stratified analysis was performed based on baseline cartilage surface damage. Results Knees with ACL mucoid degeneration showed a greater proportion of JSL progression compared with knees with a normal ACL (64% vs 47%; P = .004). After adjustment for all demographic, clinical, radiographic, and MOAKS variables, ACL mucoid degeneration was not statistically significantly associated with JSL progression in the entire cohort (adjusted odds ratio, 1.66; 95% confidence interval: 1.00, 2.77; P = .051). In subgroup analysis, ACL mucoid degeneration was statistically significantly associated with JSL progression in participants with less baseline cartilage surface damage (maximum cartilage surface loss of ≤75% in all subregions [P = .015] and ≤4 of involved subregions with cartilage surface loss [P = .028]). Conclusion ACL mucoid degeneration in participants with or at risk for osteoarthritis is associated with progression of medial tibiofemoral compartment JSL in knees with less baseline cartilage surface area damage. © RSNA, 2018 Online supplemental material is available for this article.

Low-impact sports activities are feasible after meniscus transplantation: a systematic review

To determine sports activities achieved after meniscus transplantation and if associations exist between sports activity levels and transplant failure or progression of tibiofemoral osteoarthritis (OA). A systematic search was performed using PubMed and Cochrane online databases. Inclusionary criteria were English language, clinical trials published from 1996 through May 2017, minimum 2years of follow-up, and sports activity data reported. Twenty-eight studies were included in which 1521 menisci were implanted into 1497 patients. The mean age was 34.3±6.7years, and the mean follow-up was 5.0±3.7years. Details on sports activities were provided in 7 studies (285 patients) that reported 70-92% of patients returned to a wide variety of sports activities. Mean Tegner activity scores were reported in 24 investigations. The mean score was <5 in 58% of these studies, indicating many patients were participating in light recreational activities. There was no association between mean Tegner scores and transplant failure rates. A moderate correlation was found between failure rates and mean follow-up time (R=0.63). The effect of sports activity levels on progression of tibiofemoral OA could not be determined because of limited data. Only two studies determined whether symptoms occurred during sports activities; these reported 1/38 (3%) and 5/69 (7%) patients had knee-related problems. It appeared that the majority of individuals returned to low-impact athletic activities after meniscus transplantation. The short-term follow-up did not allow for an analysis on the effect of return to high-impact activities on transplant failure rates or progression of OA. IV.

Current design (onlay) PFA implants have similar complication and reoperation rates compared to those of TKA for isolated PF osteoarthritis: a systematic review with quantitative analysis

Importance Patellofemoral osteoarthritis (PFOA) is a common problem in the active population, affecting 2–11% of men and 8–24% of women over 55 years of age. Conservative measures are often ineffective, and patellofemoral arthroplasty (PFA) is an appealing solution considering that it is minimally invasive procedure, without burning any bridges if conversion to a total knee arthroplasty (TKA) is required. Objective This work aims to systematically review the current available literature on outcomes from PFA or TKA for isolated PFOA. In particular, the research questions are: (1) Is the revision surgery rate higher in PFA than in TKA? (2) Is there any difference in conversion to TKA or reoperation rates between inlay and onlay implant design? (3) What influence has tibiofemoral osteoarthritis (TFOA) progression in PFA complication rate? (4) How many PFAs are revised or converted to TKA because of TFOA progression? Evidence review A comprehensive search was performed through PubMed, Cochrane Library, Scopus, CINAHL and Google Scholar databases to search for relevant studies on PFA. Inclusion and exclusion criteria were defined. A 20-item methodological quality tool for assessing case series studies was used. Findings Thirty-seven papers were found to be case series, and one was a case–control study (PFA vs TKA). The general methodology level was weak. However, PFAs have a statistically significant higher complication and consequently reoperation rate, with a statistically significant lower survivorship rate compared to TKA for PFOA. When taking into consideration PFA implant design, those numbers were different. Newer PFA designs, contrary to old ones, showed comparable complication and revision rates to those of TKA. However, newer PFAs9 survivorship is still significantly lower than TKAs9 one. Although TFOA progression is not necessarily a complication, it represents up to one-third of the reasons for PFA requiring revision, playing a major role in implant9s survivorship. Conclusions and relevance There is a lack of high-level evidence on PFA. However, PFAs with newer implant design showed to be as reliable in terms of the complication and reoperation rate as TKA. Progression of TFOA still remains an issue, representing up to one-third of the overall complications. Level of evidence III, systematic review of level IV and V studies.

Meniscal Allograft Transplantation Does Not Prevent or Delay Progression of Knee Osteoarthritis

BackgroundMeniscal tears are common knee injuries. Meniscal allograft transplantation (MAT) has been advocated to alleviate symptoms and delay osteoarthritis (OA) after meniscectomy. We investigated (1) the long-term outcome of MAT as a treatment of symptomatic meniscectomy, (2) most important factors affecting survivorship and (3) OA progression.MethodsFrom 1989 till 2013, 329 MAT were performed in 313 patients. Clinical and radiographic results and MAT survival were evaluated retrospectively. Failure was defined as conversion to knee arthroplasty (KA) or total removal of the MAT.ResultsMean age at surgery was 33 years (15–57); 60% were males. No-to-mild cartilage damage was found in 156 cases, moderate-to-severe damage in 130. Simultaneous procedures in 118 patients included cartilage procedures, osteotomy or ACL-reconstruction. At a mean follow-up of 6.8 years (0.2–24.3years), 5 patients were deceased and 48 lost (14.6%), 186 MAT were in situ (56.5%) whilst 90 (27.4%) had been removed, including 63 converted to a KA (19.2%). Cumulative allograft survivorship was 15.1% (95% CI:13.9–16.3) at 24.0 years. In patients <35 years at surgery, survival was significantly better (24.1%) compared to ≥35 years (8.0%) (p = 0.017). In knees with no-to-mild cartilage damage more allografts survived (43.0%) compared to moderate-to-severe damage (6.6%) (p = 0.003). Simultaneous osteotomy significantly deteriorated survival (0% at 24.0 years) (p = 0.010). 61% of patients underwent at least one additional surgery (1–11) for clinical symptoms after MAT. Consecutive radiographs showed significant OA progression at a mean of 3.8 years (p<0.0001). Incremental Kellgren-Lawrence grade was +1,1 grade per 1000 days (2,7yrs).ConclusionsMAT did not delay or prevent tibiofemoral OA progression. 19.2% were converted to a knee prosthesis at a mean of 10.3 years. Patients younger than 35 with no-to-mild cartilage damage may benefit from MAT for relief of symptoms (survivorship 51.9% at 20.2 years), but patients and healthcare payers and providers should be aware of the high number of surgical re-interventions.

Patellofemoral Joint Arthroplasty: Our Experience in Isolated Patellofemoral and Bicompartmental Arthritic Knees

INTRODUCTIONIsolated patellofemoral (PF) arthritis is rare, and there is no complete agreement about the best surgical treatment. The operative treatments are total knee arthroplasty and patellofemoral replacement (PFR). The incidence of many early complications of PF arthroplasty has decreased with the introduction of newer designs. Nowadays, the main cause of revision surgery is the progression of tibiofemoral osteoarthritis. In the past, PF arthroplasty was contraindicated in patients with evidence of osteoarthritis or pain in medial or lateral tibiofemoral compartments. The improvement in implant designs and surgical techniques has allowed the addition of a monocompartmental arthroplasty for the medial or lateral tibiofemoral compartment. In this work, we evaluate our first experience with PF arthroplasty and its combination with unicompartmental knee arthroplasty.MATERIALS AND METHODSFrom May 2014 to March 2016, we treated 14 patients. An isolated PF arthroplasty was performed in six knees (five patients), and a combined PF and unicompartmental knee arthroplasty was performed in nine cases. We observed a significant improvement in the clinical and functional Knee Society Scores (KSSs) after surgery in our patients.RESULTSWe obtained good results in our cases both for clinical and functional KSSs. Patellar clunk was recorded in one case.DISCUSSION AND CONCLUSIONWe are going toward a new attitude in which partial osteoarthritic changes could be treated with partial resurfacing prosthetic solutions such as unicompartmental, bi–unicompartmental or PFR alone, or unicompartmental combined, which respects the cruciates and achieves maximal bone preservation, which is vital, particularly, for young patients.

Obesity and the absence of trochlear dysplasia increase the risk of revision in patellofemoral arthroplasty

PurposeProper indications and patient selection are of paramount importance in patellofemoral arthroplasty (PFA). Although factors predicting outcomes in total knee arthroplasty (TKA) have been studied, there are no such studies for modern PFA. This retrospective study reports the midterm clinical and radiological outcomes and survivorship of PFA, investigating the risk factors associated with poorer outcomes and higher revision rates. MethodsFifty-one patients (51 knees) with isolated patellofemoral arthritis underwent PFA with a second-generation implant. The mean follow-up duration was 4.1years (range, 2.2 to 6.1). The cohort was stratified into obese (body mass index (BMI)≥30kg/m2, n=16), overweight (BMI 25 to 29.9kg/m2, n=20) and control (BMI 18.5 to 24.9kg/m2, n=15) groups. The same cohort was stratified based on the presence (n=11) or absence (n=40) of trochlear dysplasia (TD). ResultsThe mean Knee Society objective and function scores, the Melbourne Knee score and the Physical Component Score of Short Form 36 improved significantly. Obesity was associated with no significant improvement in the Melbourne Knee score and the Knee Society function score (p>0.05), a higher incidence of radiographic outliers and lower patient satisfaction. There was no significant difference in outcomes between the TD and non-TD groups at two years (p>0.05), with a survivorship of 92.2%. Three revisions for progression of tibiofemoral osteoarthritis were noted in the non-TD and obese or overweight groups. ConclusionsPatients with obesity and the absence of TD are at a potentially higher risk of revision surgery to TKA, and they should be counselled that PFA may represent a ‘bridging’ procedure.Level of Evidence: III

External hip adduction moment and progression of medial tibiofemoral cartilage damage and bone marrow lesions in persons with knee osteoarthritis

Purpose: Gait biomechanics at the hip may affect medial joint loading at the knee in persons with knee osteoarthritis (OA). A greater external hip adduction moment (reflecting torque generation by the hip abductor muscles) during the stance phase of gait may limit excessive hip drop or trunk lean. This, in turn, may prevent excessive medial knee joint loading and eventual progression of knee OA. Little is known about the relationship between the external hip adduction moment and progression of medial tibiofemoral OA as assessed by MRI. We hypothesized that a greater magnitude of the baseline external hip adduction moment is associated with reduced risk of baseline-to-2-year progression of medial tibiofemoral cartilage damage and bone marrow lesions in persons with knee OA. Methods: Participants with knee OA, defined by osteophyte presence in at least one knee, underwent quantitative gait analysis at baseline using an 8-camera Digital Real-Time Eagle motion analysis system and force plate. Inverse dynamics were used to calculate the external hip adduction moment, normalized to %bodyweight*height. Both knees underwent 3.0T MRI at baseline and two year follow-up using double oblique coronal and axial FLASHwe, coronal T1-weighted spin-echo (SE), and sagittal, axial and coronal fat-suppressed turbo spin echo sequences. We assessed cartilage damage and bone marrow lesions using WORMS scoring, blinding readers to hypotheses and all other data. We used logistic regression statistical models with generalized estimating equations (GEE) to account for correlation between the 2 limbs of each person, to assess the association between external hip adduction moment at baseline and baseline-to-2-year cartilage damage progression and bone marrow lesion progression, defined as any worsening of score in the medial compartment as a whole and within each joint surface. Analyses were adjusted for gait speed, age, gender, and disease severity (using K/L radiographic grade). Results are reported as odds ratios (ORs) and 95% confidence intervals (CIs). Results: 204 persons [mean age 64.2 years (±9.9, SD), mean BMI 28.5 kg/m2 (±5.7), 76.5% women] contributing 391 knees comprised the study sample. The mean external hip adduction moment was 4.43 (±0.9, SD) %body weight*height. As shown in Table 1, a greater external hip adduction moment was significantly associated with a reduced likelihood of cartilage damage progression in the medial tibiofemoral compartment and also at the medial femoral surface. After adjustment for the indicated covariables, these associations were no longer statistically significant at the 5% level. Table 2 shows the means (±SD) of the external hip adduction moment at baseline for knees with and without cartilage damage and bone marrow lesion progression in specific subregions. In analyses of specific regions, a greater external hip adduction moment was significantly associated with a reduced likelihood of cartilage damage progression at the posterior femoral subregion [OR per 1 unit of external hip adduction moment (95% CI): 0.51 (0.31, 0.86)] and bone marrow lesion progression at the central femoral subregion [OR per 1 unit (95% CI): 0.56 (0.35, 0.89)]. Conclusions: In persons with knee osteoarthritis, a greater external hip adduction moment was associated with a reduced likelihood of 2-year medial tibiofemoral cartilage damage progression and bone marrow lesion progression, but these findings were no longer statistically significant in adjusted analyses. The consistently protective direction of the findings at compartment, joint surface, and subregional levels warrants further evaluation at longer follow-up.Table 1Unadjusted and adjusted ORs (95% CIs) for medial tibiofemoral OA progression at 2 yearsMedial Tibiofemoral CompartmentMedial Femoral SurfaceMedial Tibial SurfaceCartilage damage progressionBone marrow lesion progressionCartilage damage progressionBone marrow lesion progressionCartilage damage progressionBone marrow lesion progressionNumber of knees (%) with progression61/391 (16%)87/391 (22%)48/391 (12%)53/391 (14%)29/391 (7%)48/391 (12%)Baseline predictorExternal Hip Adduction Moment (%BW*HT)Unadjusted0.70 (0.51, 0.97)0.75 (0.55, 1.01)0.68 (0.50, 0.93)0.72 (0.48, 1.08)0.88 (0.59, 1.32)0.96 (0.67, 1.37)Adjusted*0.82 (0.58, 1.15)0.85 (0.61, 1.17)0.79 (0.56, 1.12)0.80 (0.53, 1.21)1.07 (0.70, 1.64)1.20 (0.83, 1.75)Results are per 1 unit (%BW*HT) of external hip adduction moment (n = 391 knees from 204 persons)*adjusted for gait speed, age, gender, and K/L grade Open table in a new tab Table 2Means (SD) for the external hip adduction moment in medial tibial and femoral subregionsExternal Hip Adduction Moment (%BW*HT), mean (SD)Cartilage damage progression at 2-year follow-upPosterior femurCentral femurPosterior tibiaCentral tibiaAnterior tibiaNumber of knees (%) with progression20/391 (5%)33/391 (8%)7/391 (2%)25/391 (6%)8/391 (2%)Knees without progression, mean (SD)4.45 (0.88)4.44 (0.90)4.43 (0.89)4.43 (0.89)4.43 (0.89)Knees with progression, mean (SD)3.97 (0.85)4.36 (0.67)3.98 (0.57)4.32 (0.79)4.61 (0.87)Bone marrow lesion progression at 2-year follow-upNumber of knees (%) with progression19/391 (5%)38/391 (10%)12/391 (3%)33/391 (8%)21/391 (5%)Knees without progression, mean (SD)4.43 (0.87)4.47 (0.87)4.43 (0.89)4.44 (0.89)4.43 (0.88)Knees with progression, mean (SD)4.38 (1.19)4.05 (0.92)4.38 (0.84)4.34 (0.79)4.52 (0.96) Open table in a new tab Results are per 1 unit (%BW*HT) of external hip adduction moment (n = 391 knees from 204 persons) *adjusted for gait speed, age, gender, and K/L grade

Prospective evaluation of anatomic patellofemoral inlay resurfacing: clinical, radiographic, and sports-related results after 24 months.

To prospectively evaluate the clinical, radiographic, and sports-related outcomes at 24 months after isolated and combined patellofemoral inlay resurfacing (PFIR). Between 2009 and 2010, 29 consecutive patients with patellofemoral osteoarthritis (OA) were treated with the HemiCAP(®) Wave Patellofemoral Resurfacing System (Arthrosurface, Franklin, MA, USA). Based on preoperative findings, patients were divided into two groups: group I, isolated PFIR (n = 20); and group II, combined PFIR with concomitant procedures to address patellofemoral instability, patellofemoral malalignment, and tibiofemoral malalignment (n = 9). Patients were evaluated preoperatively and at 24 months postoperatively. Clinical outcomes included WOMAC, subjective IKDC, Pain VAS, Tegner activity score, and a self-designed sports questionnaire. Kellgren-Lawrence grading was used to assess progression of tibiofemoral OA. The Caton-Deschamps Index was used to assess differences in patellar height. Twenty-seven patients (93 %) were available for 24-month follow-up. Eighty-one per cent of the patients were either satisfied or very satisfied with the overall outcome. Significant improvements in the WOMAC, subjective IKDC, and Pain VAS were seen in the overall patient cohort and in both subgroups. The median Tegner score and sports frequency showed a significant increase in the overall patient cohort and in group II. The number of sports disciplines increased significantly in both subgroups. No significant progression of tibiofemoral OA or changes in patellar height were observed. Patellofemoral inlay resurfacing is an effective and safe procedure in patients with symptomatic patellofemoral OA. Significant improvements in functional scores and sports activity were found after both isolated and combined procedures. Prospective case series, Level III.

Mid-term results of the FPV patellofemoral joint replacement

BackgroundIsolated patellofemoral joint osteoarthritis affects approximately 10% of patients aged over 40years and treatment remains controversial. The Femoro Patella Vialli (FPV) patellofemoral joint replacement (Wright Medical Technology, UK) has been shown to restore functional kinematics of the knee close to normal. Despite its increasing popularity in recent years, there are no studies evaluating the mid-term results with an objective scoring assessment. AimsTherefore, the aim of this study was to report the clinical and radiological outcomes of FPV patellofemoral joint replacement in patients with isolated patellofemoral arthritis. MethodsBetween 2006 and 2012, we performed 53 consecutive FPV patellofemoral arthroplasties in 41 patients with isolated patellofemoral joint osteoarthritis. The mean follow-up was 3years. ResultsMean Oxford Knee Scores improved from 19.7 to 37.7 at latest follow-up. The progression of tibiofemoral osteoarthritis was seen 12% of knees. Two knees required revision to TKR at 7months post-operatively, which we attribute to poor patient selection. We had no cases of maltracking patellae, and no lateral releases were performed. ConclusionOur findings suggest the FPV patellofemoral prosthesis provides good pain relief and survivorship with no significant maltracking patellae.

Prediction of progression of radiographic knee osteoarthritis using tibial trabecular bone texture

To develop a system for predicting the progression of radiographic knee osteoarthritis (OA) using tibial trabecular bone texture. We studied 203 knees with (n = 68) or without (n = 135) radiographic tibiofemoral OA in 105 subjects (90 men and 15 women with a mean age of 54 years) in whom 2 sets of knee radiographs were obtained 4 years apart. We determined medial and lateral compartment tibial trabecular bone texture using an automated region selection method. Three texture parameters were calculated: roughness, degree of anisotropy, and direction of anisotropy based on a signature dissimilarity measure method. We evaluated tibiofemoral OA progression using a radiographic semiquantitative outcome: an increase in the medial joint space narrowing (JSN) grade. We examined the predictive ability of trabecular bone texture in knees with and those without preexisting radiographic OA, with adjustment for age, sex, and body mass index, using logistic regression (generalized estimating equations) and receiver operating characteristic curves. The prediction of increased medial JSN in knees with or without preexisting radiographic OA was the most accurate for medial trabecular bone texture; the area under the curve (AUC) was 0.77 and 0.75, respectively. For lateral trabecular bone texture, the AUC was 0.71 in knees with preexisting OA and 0.72 in knees without preexisting OA. We have developed a system, based on analyzing tibial trabecular bone texture, which yields good prediction of loss of tibiofemoral joint space. The predictive ability of the system needs to be further validated.

Varus and valgus alignment and incident and progressive knee osteoarthritis

ObjectiveVarus and valgus alignment increase medial and lateral tibiofemoral load. Alignment was associated with tibiofemoral osteoarthritis progression in previous studies; an effect on incident osteoarthritis risk is less certain. This...

Patellofemorale Endoprothetik in Deutschland – eine Standortbestimmung und Überblick über die Literatur

Isolated patellofemoral arthroplasty is discussed controversially. The aim of this nation-wide survey in Germany and review of the literature was to determine the current status of patellofemoral arthroplasty. A standardised questionnaire was sent to 744 German departments of orthopaedic surgery, traumatology and general surgery. In the first part, surgeons were asked general questions about their department size, case numbers of knee arthroplasties per year and non-endoprosthetic treatment of isolated patellofemoral disorders. If patellofemoral arthroplasty was conducted, parameters concerning age, gender, duration of complaints, indication for surgery, surgical approach, type of endoprosthesis used, additional surgical treatments and failures were evaluated in the second part. Furthermore we asked for the reasons if no isolated patellofemoral arthroplasty was performed. A systematic review of the literature was done including studies published until October 2007. The main inclusion criterion was the presentation of results after the implantation of a patellofemoral prosthesis for isolated patellofemoral osteoarthritis. A total of 225 analysable questionnaires were returned. Of 53,420 knee arthroplasties performed per year, only 195 (0.37 %) were isolated patellofemoral arthroplasties. The majority of patients (91 %) were between 40 and 80 years old. The aetiology of isolated patellofemoral osteoarthritis was believed to be idiopathic in 41 % and traumatic in 8 %. Patellofemoral dysplasia was held to be responsible in 47 % and patellofemoral instability in 4 % of the cases. The main reason for failure and surgical revision was ongoing tibiofemoral osteoarthritis of the affected knee. Negative attitude and disbelief towards the success of isolated patellofemoral arthroplasty were stated by the majority (62 %) of non-users. A lack of appropriate indications was reported by 22 % and lacking know-how by 16 %. We analysed 12 studies (459 implantations; 390 patients) in the literature review. The treatment was considered successful in 67.8 % of cases. The overall revision rate was 30.3 %. The highest failure rates were in patients with progression of tibiofemoral osteoarthritis or malalignment. Isolated patellofemoral arthroplasty has only low significance among surgeons performing knee arthroplasty in Germany. The majority of surgeons do not believe in the success of the procedure. Almost one third of published cases in the literature needed to be revised.

Arthritis progression after patellofemoral joint replacement

Progressive symptomatic tibiofemoral osteoarthritis (OA) following patellofemoral joint replacement (PFJR) may necessitate revision to total knee arthroplasty. This study was designed to quantify this problem in a prospective series of 103 consecutive patients who underwent PFJRs undertaken at our institution.At a mean follow-up of 7.1 years (66–102 months), 14 knees (14%) have been revised, 12 of those (12%) because of the development of symptomatic tibiofemoral OA, with a mean time to revision of 55 months (range 14 to 95 months).Available radiographs of the 89 unrevised knees were subject to blinded and randomised assessment by two observers. Postoperative AP knee radiographs were scored to assess for tibiofemoral OA progression, with definite progression seen in a median of 7% of medial compartments but 0% of lateral compartments, over a mean period of 51 months. Sulcus angles on preoperative 30° skyline radiographs were measured to assess for trochlear dysplasia. Seventeen percent of the knees without preoperative trochlear dysplasia have been revised for progression of tibiofemoral OA, compared to none of the knees with preoperative trochlear dysplasia. Furthermore, in the unrevised knees, statistically significantly more radiographic progression of tibiofemoral OA was seen in those without preoperative trochlear dysplasia (p=0.01).Our results suggest that progressive tibiofemoral OA following PFJR is an important cause of failure, but it is seen significantly less frequently when the patellofemoral arthritis is secondary to dysplasia of the femoral trochlea, suggesting that these patients are the ideal candidates for PFJR.

Hip abduction moment and protection against medial tibiofemoral osteoarthritis progression

To test the hypothesis that a greater peak internal hip abduction moment is associated with a reduced likelihood of ipsilateral medial tibiofemoral osteoarthritis (OA) progression. Fifty-seven persons with knee OA (by definite osteophyte presence and symptoms) were evaluated. Baseline assessments included kinematic and kinetic gait parameters, obtained with an optoelectronic camera system and force platform, with inverse dynamics used to calculate 3-dimensional moments at the joints; pain, using a separate visual analog scale for each knee; and alignment, using full-limb radiographs. Radiographs of the knee in a semiflexed position, with fluoroscopic confirmation of tibial rim alignment, were obtained at baseline and 18 months later. Disease progression was defined as worsening of the grade of medial joint space narrowing. Logistic regression obtained with generalized estimating equations was used to estimate odds ratios (ORs) for progression per unit of hip abduction moment, after excluding knees with the worst joint space grade at baseline (which could not progress). The 57 participants (63% women) with mild to moderate OA had a mean age of 67 years and a mean body mass index of 29. A greater internal hip abduction moment during gait was associated with a reduced likelihood of medial tibiofemoral OA progression, with OR/unit hip abduction moment of 0.52 and a 95% confidence interval (95% CI) of 0.32-0.85. This protective effect persisted after adjustment for age, sex, walking speed, knee pain severity, physical activity, varus malalignment severity, hip OA presence, and hip OA symptom presence, with an adjusted OR of 0.43 a 95% CI of 0.22-0.81. A greater hip abduction moment during gait at baseline protected against ipsilateral medial OA progression from baseline to 18 months. The likelihood of medial tibiofemoral OA progression was reduced 50% per 1 unit of hip abduction moment.