Correlation of WOMAC and KOOS scores to tibiofemoral cartilage loss on plain radiography and 3 Tesla MRI: data from the osteoarthritis initiative

Symptoms indicative of early knee osteoarthritis after ACL reconstruction: descriptive analysis of the SHIELD cohort

Objective

To describe the SHIELD cohort in terms of symptoms indicative of early knee osteoarthritis (OA) and to investigate associations between patient characteristics (demographics, activity/injury-related) and these symptoms at 1 (cross-sectional) and 3 years (longitudinal) post anterior cruciate ligament reconstruction (ACLR).

Method

106 participants (50 ​% women, mean [SD] age 25 [5] years) were included. Symptoms indicative of early knee OA were evaluated by the Knee injury and Osteoarthritis Outcome Score (KOOS) subscale pain, KOOS subscale pain ≤72 (KOOSpain ≤72), and ≤85 on two out of four KOOS subscales (pain, symptoms, activity of daily living, quality of life) (modified Luyten).

Results

Mean (SD) KOOS pain scores were 83.2 (15.7) and 87.3 (12.7) at 1 and 3 years, respectively. At 1 year and 3 years post ACLR, 18/101 (18 ​%) and 14/86 (16 ​%) participants met the KOOSpain ≤72 criterion, whereas 83/101 (82 ​%) and 67/86 (78 ​%) met the modified Luyten criterion. 7/15 (47 ​%) (KOOSpain ≤72) and 59/70 (84 ​%) (modified Luyten) classified as having knee OA symptoms 1 year post ACLR were still classified as having OA symptoms after 3 years. Lower activity level at 1 year was the sole variable consistently associated with all three outcomes 3 years post ACLR.

Conclusion

The proportion of participants fulfilling existing classification criteria for symptoms indicative of early OA after ACLR is highly dependent on the criteria applied and different criteria seem to capture varying aspects of early OA symptoms. Future studies will reveal if these symptoms will persist long-term or just reflect more transient issues.

Correlation between proprioception, functionality, patient-reported knee condition and joint acoustic emissions

Non-invasive assessment of joint status using acoustic emissions (AE) is a growing research area that has the potential to translate into clinical practice. The purpose of this study is to investigate the correlation of the knee's AE with measures of proprioception, self-assessment, and performance, as it can be hypothesised that, AE parameters will correlate with joint function metrics due to AE being recorded during interaction of the articular surfaces. Threshold to detect passive motion (TTDPM), Knee Osteoarthritis Outcome Scores (KOOS) and 5 times sit-to-stand test (5STS) were collected from 51 participant. Knee AE were recorded during cycling with 30 and 60 rpm cadences using two sensors in different frequency ranges and three modes of AE event detection. Weak (0.297, p = 0.048) to moderate (0.475, p = 0.001) Spearman's correlations were observed between longer 5STS time and AE parameters (i.e. higher median absolute energy, signal strength, longer AE event rise time and duration). Similarly, AE parameters shown correlation with lower KOOS, especially in the "Function in Sports and Recreation" and "Activities of Daily Living" subscales with correlation coefficients for higher median amplitude up to 0.441, p = 0.001 and 0.403, p = 0.004, respectively. The correlation with the TTDPM was not detected for most of the AE parameters. Additionally, a lower frequency sensor and 60 rpm cadence AE recordings showed higher correlations. Considering that this study included subjects from the general population and the number of participants with KOOS <70 was relatively small, higher correlations might be expected for clinically confirmed OA cases. Additionally, different ICCs might be expected for alternative signal parameters and proprioception assessment methods. Overall, the study confirms that AE monitoring offers an additional modality of joint assessment that reflects interaction between cartilage surfaces and can complement orthopaedic diagnostics, especially in the context of remote monitoring, drug testing, and rehabilitation.

High prevalence of associated injuries in anterior cruciate ligament tears: A detailed magnetic resonance imaging analysis of 254 patients

OBJECTIVES

To evaluate the type and prevalence of associated injuries by using magnetic resonance imaging (MRI) in patients with anterior cruciate ligament (ACL) tears.

METHODS

Data from the Natural Corollaries and Recovery after ACL injury multicenter longitudinal cohort study were analyzed. Between May 2016 and October 2018, patients aged between 15 and 40 years, who had experienced an ACL tear within the last 6 weeks and sought medical attention at one of seven healthcare clinics in Sweden, were invited to participate. The mean time from injury to MRI was 19.6 ± 15.2 days. An orthopedic knee surgeon and a musculoskeletal radiologist reviewed all the MRI scans. The following structures were assessed: posterior cruciate ligament (PCL), medial collateral ligament (MCL) complex, lateral collateral ligament (LCL), popliteus tendon, medial meniscus (MM), lateral meniscus (LM), and cartilage. In addition, the presence of bone bruising, impaction fractures in the lateral femoral condyle (LFC) or posterolateral tibia (PLT), and Segond fractures were also assessed.  RESULTS: A total of 254 patients (48.4% males) with a mean age of 25.4 ± 7.1 years were included. The prevalence of associated injuries was as follows: PCL (0.4%), MCL {41.3% [superficial MCL and deep MCL (dMCL) 16.5%; isolated dMCL 24.8%]}, LCL (2.4%), MM (57.4%), LM (25.2%), cartilage (15.0%), bone bruising (92.9%), impaction fracture in the LFC (45.7%) and PLT (4.7%), and Segond fracture (7.5%).

CONCLUSIONS

The prevalence of associated injuries in patients with ACL tears was high. The findings reported in this study may serve as a reference tool for orthopedic surgeons and radiologists in the diagnosis of associated injuries using MRI in patients with ACL tears.

Investigating the relationship between radiographic joint space width loss and deep learning-derived magnetic resonance imaging-based cartilage thickness loss in the medial weight-bearing region of the tibiofemoral joint

Objective

To investigate the relationship between measures of radiographic joint space width (JSW) loss and magnetic resonance imaging (MRI)-based cartilage thickness loss in the medial weight-bearing region of the tibiofemoral joint over 12-24 months. To stratify this relationship by clinically meaningful subgroups (sex and pain status).

Design

We analyzed a subset of knees (n ​= ​256) from the Osteoarthritis Initiative (OAI) likely in early stage OA based on joint space narrowing (JSN) measurements. Natural logarithm transformation was used to approximate near normal distributions for JSW loss. Pearson Correlation coefficients described the relationship between ln-transformed JSW loss and several versions of deep learning-derived MRI-based cartilage thickness loss parameters (minimum, maximum, and mean) in subregions of the femoral condyle, tibial plateau, and combined femoral and tibial regions. Linear mixed-effects models evaluated the associations between the ln-transformed radiographic and MRI-derived measures including potential confounders.

Results

We found weak correlations between ln-transformed JSW loss and MRI-based cartilage thickness ranging from R ​= ​-0.13 (p ​= ​0.20) to R ​= ​0.26 (p ​< ​0.01). Correlations were higher (still poor) among females compared to males and painful compared to non-painful knees. Model results showed weak associations for nearly all MRI-based measures, ranging from no association to β (95% CI) ​= ​0.25 (0.11, 0.39). Associations were higher among females compared to males and minimal differences between painful and non-painful knees.

Conclusions

Despite its recommended use in disease-modifying OA drug clinical trials, results suggest that JSW loss is an ineffective proxy measure of cartilage thickness loss over 12-24 months and within a localized region of the tibiofemoral joint.

Extent of posterolateral tibial plateau impaction fracture correlates with anterolateral complex injury and has an impact on functional outcome after ACL reconstruction

PURPOSE

The impact of posterolateral tibial plateau impaction fractures (TPIF) on posttraumatic knee stability in the setting of primary anterior cruciate ligament (ACL) tear is unknown. The main objective was to determine whether increased bone loss of the posterolateral tibial plateau is associated with residual rotational instability and impaired functional outcome after ACL reconstruction.

METHODS

A cohort was identified in a prospective enrolled study of patients suffering acute ACL injury who underwent preoperative standard radiographic diagnostics and clinical evaluation. Patients were included when scheduled for isolated single-bundle hamstring autograft ACL reconstruction. Exclusion criteria were concurrent anterolateral complex (ALC) reconstruction (anterolateral tenodesis), previous surgery or symptoms in the affected knee, partial ACL tear, multi-ligament injury with an indication for additional surgical intervention, and extensive cartilage wear. On MRI, bony (TPIF, tibial plateau, and femoral condyle morphology) and ligament status (ALC, concomitant collateral ligament, and meniscus injuries) were assessed by a musculoskeletal radiologist. Clinical evaluation consisted of KT-1000, pivot-shift, and Lachman testing, as well as Tegner activity and IKDC scores.

RESULTS

Fifty-eight patients were included with a minimum follow-up of 12 months. TPIF was identified in 85% of ACL injuries (n = 49). The ALC was found to be injured in 31 of 58 (53.4%) cases. Pearson analysis showed a positive correlation between TPIF and the degree of concomitant ALC injury (p < 0.001). Multiple regression analysis revealed an increased association of high-grade TPIF with increased lateral tibial convexity (p = 0.010). The high-grade TPIF group showed worse postoperative Tegner scores 12 months postoperatively (p = 0.035).

CONCLUSION

Higher degrees of TPIFs are suggestive of a combined ACL/ALC injury. Moreover, patients with increased posterolateral tibial plateau bone loss showed lower Tegner activity scores 12 months after ACL reconstruction.

LEVEL OF EVIDENCE

III.

A Retrospective Analysis of Characteristic Features of Responders and Impaired Patients to a Single Injection of Pure Platelet-Rich Plasma in Knee Osteoarthritis

(1) Background: The emergence of injectable “biologic” medication creates a new approach to treat osteoarthritis (OA). Among them, the use of intra-articular injection of PRP became widespread despite the absence of consensus regarding its optimal composition. The aim of this study was to retrospectively correlate an extensive biological characterization of injected PRP to the clinical responses of patients presenting knee OA. (2) Methods: This retrospective study included 75 patients with knee OA. Cartilage lesions were assessed using magnetic resonance imaging and the International Cartilage Regeneration Society (ICRS) classification. PRP extensive biological characterization was performed and patients’ subjective symptoms were recorded before injection and 3 and 6 months after injection using the Knee injury and Osteoarthritis Outcome Score (KOOS). Responders were defined by an improvement of 10 points on KOOS. (3) Results: At 6 months, 63.0% of the patients were responders. Impairment was characterized by a significantly higher proportion of patients with three compartments altered at baseline MRI and receiving a significantly higher dose of platelets compared to responders. (4) Conclusions: Single injection of pure PRP resulted in significant clinical improvement in the management of knee OA. Both baseline MRI and PRP biological features may be predictive factors of the clinical response, highlighting that a better understanding of action mechanism of PRP is still required.

Femoral and tibial bone bruise volume is not correlated with ALL injury or rotational instability in patients with ACL-deficient knee

PURPOSE

Some researchers have suggested that bone bruises are evidence of rotational instability. The hypothesis was that the extent of lateral bone edema is correlated with the presence of an anterolateral ligament (ALL) injury. The main objective was to determine whether there was a correlation between the presence of an ALL injury the extent of bone bruises.

METHODS

A prospective diagnostic study enrolled all the patients who suffered an acute anterior cruciate ligament (ACL) who were operated on within 8 weeks. The extent of bone bruising according to the ICRS classification was measured on preoperative MRIs by two independent blinded raters twice with an interval of 4 weeks. Dynamic ultrasonography (US) to look for ALL injury and the pivot shift test were performed before the ACL surgery. The correlation between ALL injury and bone bruises, and the correlation between an ALL injury and a high-grade pivot shift test were determined.

RESULTS

Sixty-one patients were included; 52% of patients had an ALL injury on US. The extent of lateral bone bruise was not related to the presence of an ALL injury, nor related to the presence of a high-grade pivot shift. A grade 2 or 3 pivot shift was significantly correlated with an ALL injury (p < 0.0001). Inter- and intra-rater reliability for the bone bruise rating was excellent.

CONCLUSION

The extent of lateral bone bruise is not correlated with ALL injury or a high-grade pivot shift; thus, it is not correlated with rotational instability of the knee.

LEVEL OF EVIDENCE

II.

Pain and knee damage in male and female mice in the medial meniscal transection-induced osteoarthritis

OBJECTIVE

To investigate sex effects on pain-related behaviors in the medial meniscal transection (MMT) knee osteoarthritis (OA) model.

METHODS

Experiments were performed in male and female C57BL/6J mice (12/group/sex). MMT was induced by transection of the medial collateral ligament and the medial meniscus. Sham-operated and naïve mice served as controls. Mechanical and heat sensitivity in hind paws, hind limb use, and locomotor activity were measured for 3 months. Knee histology was performed on week 12.

RESULTS

In males, MMT triggered a bi-phasic mechanical hypersensitivity and decreased load on OA limb, with an acute post-operative (1-5 days) and chronic (3-12 weeks) OA phases separated by a remission in the intermediate phase (1-2 weeks). Females showed a less pronounced bi-phasic pattern, with a greater mechanical hypersensitivity, but not poorer limb use, than males in the intermediate phase (maximal difference: 1.1 g, 95% confidence intervals (CI) [0.7, 1.5]). There were no major sex differences in the chronic phase. MMT did not induce heat hypersensitivity or change in locomotor activity in the chronic phase in both sexes. MMT caused more severe cartilage damage in males than in females (maximal difference: 1.1 score points, 95% CI [1.9, 0.3]), and a comparable between sexes osteophyte formation. The knee damage did not correlate with pain.

CONCLUSIONS

MMT modelled human knee OA well, capturing cartilage destruction and osteophyte formation, mechanical pain, and poorer limb use in both sexes. Sex differences in pain were modality- and time-dependent, reflecting complex sex-related features of human OA.

What is the Likelihood of Subsequent Arthroplasties after Primary TKA or THA? Data from the Osteoarthritis Initiative

BACKGROUND

Osteoarthritis is common and debilitating, in part because it often affects more than one large weightbearing joint. The likelihood of undergoing more than one total joint arthroplasty has not been studied in a heterogeneous, multicenter population in the United States.

QUESTIONS/PURPOSES

We used prospectively collected data of patients with osteoarthritis from the multicenter Osteoarthritis Initiative (OAI) project to ask (1) What is the likelihood of a subsequent THA or TKA after primary TKA or THA? (2) What risk factors are associated with undergoing contralateral TKA after primary TKA?

METHODS

Longitudinally maintained data from the OAI were used to identify 332 patients who underwent primary TKA and 132 patients who underwent primary THA for osteoarthritis who did not have a previous TKA or THA in this retrospective study. OAI was a longitudinal cohort study of knee osteoarthritis conducted at five centers in the United States (Columbus, OH, USA; Pittsburgh, PA, USA; Baltimore, MD, USA; Pawtucket, RI, USA; and San Francisco, CA, USA). In this study, the mean follow-up time was 4.0 ± 2.3 years, with 24% (112 of 464) followed for less than 2 years. The primary outcome was the cumulative incidence of subsequent arthroplasty calculated using the Kaplan-Meier method. Age, BMI, gender, and contralateral Kellgren-Lawrence grade, medial joint space width, and hip-knee-ankle angles were modeled as risk factors of contralateral TKA using Cox proportional hazards.

RESULTS

Using the Kaplan-Meier method, at 8 years the cumulative incidence of contralateral TKA after the index TKA was 40% (95% CI 31 to 49) and the cumulative incidence of any THA after index TKA was 13% (95% CI 5 to 21). The cumulative incidence of contralateral THA after the index THA was 8% (95% CI 2 to 14), and the cumulative incidence of any TKA after index THA was 32% (95% CI 15 to 48). Risk factors for undergoing contralateral TKA were younger age (HR 0.95 for each year of increasing age [95% CI 0.92 to 0.98]; p = 0.001) and loss of medial joint space width with a varus deformity (HR 1.26 for each 1 mm loss of joint space width at 1.6 varus [1.06 to 1.51]; p = 0.005).

CONCLUSION

Patients who underwent TKA or THA for osteoarthritis had a high rate of subsequent joint arthroplasties in this study conducted at multiple centers in the United States. The rate of subsequent joint arthroplasty determined in this study can be used to counsel patients in similar settings and institutions, and may serve as a benchmark to assess future osteoarthritis disease-modifying interventions.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Tibiofemoral bone bruise volume is not associated with meniscal injury and knee laxity in patients with anterior cruciate ligament rupture

PURPOSE

This study aimed at evaluating the association between the volume of the bone bruises and the magnitude of knee sagittal laxity and presence of meniscal injury in patients with anterior cruciate ligament (ACL) rupture. It was hypothesized that higher volumes of bone bruises will be associated with increased knee laxity and the presence of meniscal injury.

METHODS

Patients with clinical diagnosis of ACL injury were referred for magnetic resonance imaging (MRI) and knee sagittal laxity measurement with a mechanical instrumented device (Porto-Knee Testing Device). The femoral and tibial bone bruises were assessed by MRI and the volume measured by manually contouring the bone bruise using a computerized software and computed by a mathematical algorithm combining all measured areas. The ACL rupture type (partial or total), meniscal tear (medial or lateral), and the localization of bone bruise were also analyzed.

RESULTS

Seventy-six ACL-ruptured participants were included and 34 patients displayed bone bruises. Tibiofemoral sagittal laxity was higher in participants with complete ACL rupture (p < 0.05), but not influenced by the volume of bone bruises and meniscal status (n.s.). The volume of bone bruises was not significantly associated with the meniscal lesion or with the tibiofemoral sagittal laxity, independently of the meniscal injury status (n.s.).

CONCLUSIONS

The volume of femoral and/or tibial bone bruises was not associated with the type of ACL injury, tibiofemoral sagittal laxity or the status of meniscal injury. Bone bruises must be considered as a radiographic sign of injury and should not be suggestive of injury severity and not overvalued.

LEVEL OF EVIDENCE

Retrospective cohort study, Level III.

IRB NUMBER

0011/0014.

Bone bruise in anterior cruciate ligament rupture entails a more severe joint damage affecting joint degenerative progression

PURPOSE

During anterior cruciate ligament (ACL) injury, the large external forces responsible for ligament rupture cause a violent impact between tibial and femoral articular cartilage, which is transferred to bone resulting in bone bruise detectable at MRI. Several aspects remain controversial and await evidence on how this MRI finding should be managed while addressing the ligament lesion. Thus, the aim of the present review was to document the evidence of all available literature on the role of bone bruise associated with ACL lesions.

METHODS

A systematic review of the literature was performed on bone bruise associated with ACL injury. The search was conducted in September 2017 on three medical electronic databases: PubMed, Web of Science, and the Cochrane Collaboration. Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines were used. Relevant articles were studied to investigate three main aspects: prevalence and progression of bone bruise associated with ACL lesions, its impact on the knee in terms of lesion severity and joint degeneration progression over time and, finally, the influence of bone bruise on patient prognosis in terms of clinical outcome.

RESULTS

The search identified 415 records and, after an initial screening according to the inclusion/exclusion criteria, 83 papers were used for analysis, involving a total of 10,047 patients. Bone bruise has a high prevalence (78% in the most recent papers), with distinct patterns related to the mechanism of injury. This MRI finding is detectable only in a minority of cases the first few months after trauma, but its presence and persistence have been correlated to a more severe joint damage that may affect the degenerative progression of the entire joint, with recent evidence suggesting possible effects on long-term clinical outcome.

CONCLUSION

This systematic review of the literature documented a growing interest on bone bruise associated with ACL injury, highlighting aspects which could provide to orthopaedic surgeons evidence-based suggestions in terms of clinical relevance when dealing with patients affected by bone bruise following ACL injury. However, prospective long-term studies are needed to better understand the natural history of bone bruise, identifying prognostic factors and targets of specific treatments that should be developed in light of the overall joint derangements accompanying ACL lesions.

LEVELS OF EVIDENCE

IV, Systematic review of level I-IV studies.

Subchondral Bone and the Osteochondral Unit: Basic Science and Clinical Implications in Sports Medicine

Context:

Articular cartilage injuries and early osteoarthritis are among the most common conditions seen by sports medicine physicians. Nonetheless, treatment options for articular degeneration are limited once the osteoarthritic cascade has started. Intense research is focused on the use of biologics, cartilage regeneration, and transplantation to help maintain and improve cartilage health. An underappreciated component of joint health is the subchondral bone.

Evidence Acquisition:

A comprehensive, nonsystematic review of the published literature was completed via a PubMed/MEDLINE search of the keywords “subchondral” AND “bone” from database inception through December 1, 2016.

Study Design:

Clinical review.

Level of Evidence:

Level 4.

Methods:

Articles collected via the database search were assessed for the association of bone marrow lesions and osteoarthritis, cartilage regeneration, and ligamentous and meniscal injury; the clinical disorder known as painful bone marrow edema syndrome; and the subchondral bone as a target for medical and surgical intervention.

Results:

A complex interplay exists between the articular cartilage of the knee and its underlying subchondral bone. The role of subchondral bone in the knee is intimately related to the outcomes from cartilage restoration procedures, ligamentous injury, meniscal pathology, and osteoarthritis. However, subchondral bone is often neglected when it should be viewed as a critical element of the osteochondral unit and a key player in joint health.

Conclusion:

Continued explorations into the intricacies of subchondral bone marrow abnormalities and implications for the advent of procedures such as subchondroplasty will inform further research efforts on how interventions aimed at the subchondral bone may provide durable options for knee joint preservation.

Preoperative Tibial Subchondral Bone Marrow Lesion Patterns and Associations With Outcomes After Isolated Meniscus Allograft Transplantation

BACKGROUND

The association between preoperative tibial subchondral bone marrow lesion (BML) patterns and outcomes after isolated meniscus allograft transplantation (MAT) are unknown.

PURPOSE

To determine (1) if a superior classification means exists (ie, high interrater reliability [IRR]) for grading tibial subchondral BML before isolated MAT and (2) whether quality and/or severity of preoperative tibial subchondral BML patterns was associated with clinical outcomes and/or failure rates after isolated MAT.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

All patients who underwent isolated MAT with a single surgeon between October 2006 and February 2017 were identified. Three means were evaluated to quantify the degree of subchondral BML in the affected tibial-sided compartment: Welsch et al, based on maximum diameter of the lesion; Costa-Paz et al, based on appearance and location of the lesion; and Filardo et al, based on severity of findings. IRR was generated and compared among the 3 classifications. The preoperative magnetic resonance imaging (MRI) subchondral BML grading scheme with the highest IRR was then used to assess for associations with postoperative outcomes for those patients with >2-year follow-up, per a Spearman correlation matrix with each reviewer's grades.

RESULTS

In total, 60 MRI scans were available for subchondral BML grading. Grader 1 identified the presence of subchondral BML in the tibia of the affected compartment in 40 (66.7%) of the available MRI scans, as compared with 38 (63.3%) for grader 2. The calculated IRRs with the Welsch et al and Costa-Paz et al classifications were rated "strong/almost perfect" agreement. A significant correlation was demonstrated between grader 1 with the Welsch et al grading scheme and outcome measures of KOOS pain (Knee injury and Osteoarthritis Outcome Score; negative correlation, P = .05), WOMAC pain (Western Ontario and McMaster Universities Osteoarthritis Index; positive correlation, P = .026), and Marx Activity Rating Scale (negative correlation, P = .019). A significant correlation was demonstrated between grader 2 with the Costa-Paz et al grading scheme and postoperative satisfaction (positive correlation, P = .018). There were no significant differences in survivorship based on gradings.

CONCLUSION

Nearly two-thirds of patients who undergo isolated MAT have subchondral BML on preoperative MRI. Our findings suggest that increasing BML size (Welsch et al) is correlated with worse postoperative pain measures (KOOS pain, WOMAC pain) and worse activity ratings (Marx Activity Rating Scale). Additionally, increasing disruption or depression of the normal contour of the cortical surface, with or without lesion contiguity with the subjacent articular surface (Costa-Paz et al), is correlated with greater postoperative satisfaction.

Preoperative KOOS and SF-36 Scores Are Associated With the Development of Symptomatic Knee Osteoarthritis at 7 Years After Anterior Cruciate Ligament Reconstruction

BACKGROUND

Anterior cruciate ligament (ACL) tears are associated with the development of knee osteoarthritis despite ACL reconstruction surgery. However, little evidence is available to determine which patients will develop symptomatic knee osteoarthritis.

PURPOSE

To determine if preoperative outcome measures-KOOS (Knee injury and Osteoarthritis Outcome Score) and SF-36 (36-item Short Form Health Survey)-were associated with the development of a symptomatic knee 7 years after ACL reconstruction. A secondary goal was to examine the relationship between imaging evidence of knee osteoarthritis and development of knee pain.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

Prospectively collected data from 72 patients were reviewed with 7-year follow-up after unilateral ACL reconstruction. Patients were divided into symptomatic and asymptomatic groups based on the previously defined KOOS pain ≤72. Demographic variables and preoperative KOOS and SF-36 scores were compared between groups. Radiographic and magnetic resonance imaging data were used to evaluate differences in joint space width, Osteoarthritis Research Society International radiographic score, and the Whole-Organ Magnetic Resonance Imaging Score between groups. Univariate and multivariate analyses were performed to identify potential predictors of pain at 7-year follow-up. Wilcoxon sum rank and t tests were used to compare imaging findings between the symptomatic and asymptomatic patients at 7 years.

RESULTS

According to KOOS pain, 7 of the 72 patients available at 7-year follow-up formed the symptomatic group. No differences were found between groups in regard to demographic variables or intraoperative findings. In multivariate analysis, lower preoperative scores for KOOS sports/recreation ( P = .005) and SF-36 mental health ( P = .025) were associated with a painful knee at 7 years, with increased odds of 82% and 68% per 10-unit decrease, respectively. The Whole-Organ Magnetic Resonance Imaging Score at 7 years showed evidence of osteoarthritic changes in the symptomatic group as compared with the asymptomatic group ( P = .047). However, there were no significant differences in the Osteoarthritis Research Society International radiographic score ( P = .051) or joint space width ( P = .488) between groups.

CONCLUSION

Lower preoperative KOOS and SF-36 scores were associated with those patients who developed symptomatic knee osteoarthritis 7 years after ACL reconstruction.

Identification of pain categories associated with change in pain in patients receiving placebo: data from two phase 3 randomized clinical trials in symptomatic knee osteoarthritis

Background

Pain is the principal clinical symptom of osteoarthritis (OA), and development of safe and effective analgesics for OA pain is needed. Drug development of new analgesics for OA pain is impaired by substantial change in pain in patients receiving placebo, and more data describing clinical characteristics and pain categories particularly associated with this phenomenon is needed.

The purpose of this post-hoc analysis was to investigate clinical characteristics and pain categories and their association with radiographic progression and placebo pain reduction (PPR) in OA patients as measured the Western Ontario and McMasters Arthritis (WOMAC).

Methods

Pooled data from the placebo groups of two phase III randomized clinical trials in patients with knee OA followed for 2 years were analyzed. Differences between individual sub-scores and pain categories of weight-bearing and non-weight bearing pain over time were assessed. Selected patient baseline characteristics were assessed for association with PPR. Association between pain categories and radiographic progression was analyzed.

Results

The reduction of pain in placebo-treated patients was significantly higher in the composite of questions related to weight-bearing pain compared to non-weight-bearing pain of the target knee. Baseline BMI, age and JSW were not associated with pain change. Pain reduction was higher in the Target knee, compared to the Non-Target knee at all corresponding time-points. A very weak correlation was found between weight-bearing pain and progression in the non-target knee.

Conclusions

These results indicate that the reduction in pain in patients treated with placebo is significantly different between pain categories, as weight-bearing pain was significantly more reduced compared to non-weight-bearing pain. Further research in pain categories in OA is warranted.

Trial Registration

NCT00486434 (trial 1) and NCT00704847 (trial 2)

Baseline Cartilage Thickness and Meniscus Extrusion Predict Longitudinal Cartilage Loss by Quantitative Magnetic Resonance Imaging: Data From the Osteoarthritis Initiative

OBJECTIVE

This study aimed to assess how meniscus damage and baseline cartilage thickness influence the rate of cartilage loss and knee pain.

METHODS

Of 4796 participants in the Osteoarthritis Initiative, 86 had baseline and 48-month follow-up quantitative magnetic resonance imaging data for medial compartment cartilage thickness. Baseline meniscus pathology was scored by a musculoskeletal radiologist using Whole-Organ Magnetic Resonance Imaging Score. Findings were correlated with 72-month Knee injury and Osteoarthritis Outcome Score.

RESULTS

Univariate analysis showed cartilage change was not influenced by demographic variables. Multivariable regression revealed that initial cartilage thickness (-1.07 mm at 48 months for every 1 mm decrease at baseline, P < 0.001) and meniscus extrusion (-0.33 mm if present at baseline, P < 0.001) were the strongest predictors of medial compartment cartilage thickness at 48 months. Knee injury and Osteoarthritis Outcome Score pain scores did not correlate with cartilage loss.

CONCLUSIONS

Baseline cartilage thickness and meniscus extrusion are important and independent predictors for accelerated cartilage loss. However, the degree of cartilage loss did not correlate with midterm change in clinical outcome scores.

Knee Donor Site Morbidity Following Harvest of Medial Femoral Trochlea Osteochondral Flaps for Carpal Reconstruction

PURPOSE

This study examines donor site morbidity associated with the medial femoral trochlea (MFT) when used as a donor site for vascularized osteochondral flaps for reconstruction of challenging carpal defects such as proximal pole scaphoid nonunion and advanced Kienböck disease.

METHODS

The retrospective study population included all patients who had undergone MFT flap harvest for scaphoid or lunate reconstruction. Chart review, patient questionnaires, and validated knee function assessment tools were used: International Knee Documentation Committee Subjective Knee Form scores ranged from 0 (maximal disability) to 100 (no disability). Western Ontario and McMaster Universities osteoarthritis index scores ranged from 0% (no disability) to 100% (maximal disability). Magnetic resonance imaging and radiographs were obtained on the donor knee on the majority of patients.

RESULTS

Questionnaire response rate was 79% (45 of 57 patients). Average patient age was 35 ± 11 years (range, 19-70 years). Average postoperative follow-up was 27 ± 17 months (range, 9-108 months). The indication for MFT flap reconstruction was scaphoid nonunion in 30 patients and Kienböck disease in 15 patients. All 45 patients had a stable knee on examination. Magnetic resonance and radiographic imaging obtained on 35 patients exhibited no pathological changes. Average duration of postoperative pain was 56 ± 59 days (range, 0-360 days); average duration until patients reported the knee returning to normal was 90 ± 60 days (range, 14-360 days). Forty-three of 44 patients would have the same surgery again if needed; overall satisfaction with the surgery was rated as 5 ± 1 (range, 2-5) on a scale from 0 (no satisfaction) to 5 (maximal satisfaction). Average International Knee Documentation Committee score was 96 ± 9 (range, 56.3-100) and the average Western Ontario and McMaster Universities score was 6% ± 16% (range, 0%-68%).

CONCLUSIONS

Medial femoral trochlea osteochondral flap harvest results in minimal donor site morbidity in the majority of patients. Symptoms are time limited. Intermediate-term follow-up demonstrates excellent results in subjective outcome measures.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Subchondral Bone Marrow Edema Had Greater Effect on Postoperative Pain After Medial Unicompartmental Knee Arthroplasty Than Total Knee Arthroplasty

BACKGROUND

Although the relationship between pain and bone marrow edema (BME) in the osteoarthritic knee has been established, little is known about the effect of preoperative BME on postoperative outcomes after knee arthroplasty or if the influence of BME on postoperative outcomes differs between medial unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA). The purpose of this study was to compare pain, patient satisfaction, and revision rates between medial UKA and TKA patients with and without magnetic resonance imaging evidence of BME in the proximal tibia.

METHODS

We identified 71 patients (72 knees) from our prospective outcomes database with magnetic resonance images taken before undergoing either medial UKA or TKA and recorded the absence or presence of tibial BME. We then compared preoperative and postoperative Knee Society pain scores, patient satisfaction, and revisions between groups of UKA and TKA patients with or without preoperative tibial BME.

RESULTS

Pain scores for UKA patients with BME were worse both before and after surgery, whereas TKA patients with BME demonstrated greater postoperative improvements in pain scores when compared to TKA patients without BME. Similarly, significantly fewer UKA patients with BME were satisfied with their procedure than those without BME (8/11, 73% vs 17/17, 100%; P = .05), but BME did not affect patient satisfaction after TKA.

CONCLUSION

Preoperative BME did not influence TKA outcomes; however, pain scores for UKA patients with BME were worse both before and after surgery and fewer UKA patients with preoperative tibial BME were satisfied with their surgery.

KOOS pain as a marker for significant knee pain two and six years after primary ACL reconstruction: a Multicenter Orthopaedic Outcomes Network (MOON) prospective longitudinal cohort study

OBJECTIVE

The prevalence of radiographic osteoarthritis (OA) after anterior cruciate ligament reconstruction (ACLR) approaches 50%, yet the prevalence of significant knee pain is unknown. We applied three different models of Knee injury and Osteoarthritis Outcome Score (KOOS) thresholds for significant knee pain to an ACLR cohort to identify prevalence and risk factors.

DESIGN

Multicenter Orthopaedic Outcomes Network (MOON) prospective cohort patients with a unilateral primary ACLR and normal contralateral knee were assessed at 2 and 6 years. Independent variables included patient demographics, validated Patient Reported Outcomes (PRO; Marx activity score, KOOS), and surgical characteristics. Models included: (1) KOOS criteria for a painful knee = quality of life subscale <87.5 and ≥2 of: KOOSpain <86.1, KOOSsymptoms <85.7, KOOSADL <86.8, or KOOSsports/rec <85.0; (2) KOOSpain subscale score ≤72 (≥2 standard deviations below population mean); (3) 10-point KOOSpain drop from 2 to 6 years. Proportional odds models (alpha ≤ 0.05) were used.

RESULTS

1761 patients of median age 23 years, median body mass index (BMI) 24.8 kg/m(2) and 56% male met inclusion, with 87% (1530/1761) and 86% (1506/1761) follow-up at 2 and 6 years, respectively. At 6 years, n = 592 (39%), n = 131 (9%) and n = 169 (12%) met criteria for models #1 through #3, respectively. The most consistent and strongest independent risk factor at both time-points was subsequent ipsilateral knee surgery. Low 2-year Marx activity score increased the odds of a painful knee at 6 years.

CONCLUSIONS

Significant knee pain is prevalent after ACLR; with those who undergo subsequent ipsilateral surgery at greatest risk. The relationship between pain and structural OA warrants further study.

Association between the severity of femoral condylar cartilage erosion related to knee osteoarthritis by ultrasonographic evaluation and the clinical symptoms and functions

OBJECTIVE

To determine the association between the severity of femoral condylar cartilage erosion resulting from knee osteoarthritis (OA) by an ultrasonographic grading system and the clinical symptoms and functions.

DESIGN

Cross-sectional study.

SETTING

A tertiary center.

PARTICIPANTS

Participants (N=101) with and without subjective complaints of knee discomfort were consecutively enrolled. Patients who had ever received knee arthroplasty, who had inflammatory arthritis, and whose knee flexion range of motion was <90° were excluded. A total of 194 knees were evaluated.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

A semiquantitative ultrasonographic grading system was used to evaluate the severity of femoral condylar cartilage erosion. The clinical symptoms and functions were evaluated with the visual analog scale (VAS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Lequesne index. The association of the VAS/WOMAC/Lequesne index with the ultrasonographic grading was assessed.

RESULTS

Positive linear associations were found between the ultrasonographic grading and the following: the VAS and the total scores and pain subscales of both the Lequesne index and WOMAC. Multivariate logistic regression analysis revealed grade-dependent association between VAS and ultrasonographic grading after adjusting for age, sex, and body mass index. The WOMAC and Lequesne index scores were associated with the ultrasonographic grading in more severe degrees, particularly in the pain subscales.

CONCLUSIONS

This semiquantitative ultrasonographic grading system may well reflect the clinical symptoms and functions related to knee OA as evaluated by the VAS, WOMAC, and Lequesne index. This method provides a more comprehensive description and measurement of knee OA.

Osteoarthritis disease progression model using six year follow-up data from the osteoarthritis initiative

The objective was to develop a quantitative model of disease progression of knee osteoarthritis over 6 years using the total WOMAC score from patients enrolled into the Osteoarthritis Initiative (OAI) study. The analysis was performed using data from the Osteoarthritis Initiative database. The time course of the total WOMAC score of patients enrolled into the progression cohort was characterized using non-linear mixed effect modeling in NONMEM. The effect of covariates on the status of the disease and the progression rate was investigated. The final model provided a good description of the experimental data using a linear progression model with a common baseline (19 units of the total WOMAC score). The WOMAC score decreased by 1.77 units/year in 89% of the population or increased by 1.74 units/year in 11% of the population. Multiple covariates were found to affect the baseline and the rate of progression, including BMI, sex, race, the use of pain medications, and the limitation in activity due to symptoms. A mathematical model to describe the disease progression of osteoarthritis in the studied population was developed. The model identified two sub-populations with increasing or decreasing total WOMAC score over time, and the effect of important covariates was quantified.

Trajectory of cartilage loss within 4 years of knee replacement--a nested case-control study from the osteoarthritis initiative

OBJECTIVE

Knee replacement (KR) represents a clinically important endpoint of knee osteoarthritis (KOA). Here we examine the 4-year trajectory of femoro-tibial cartilage thickness loss prior to KR vs non-replaced controls.

METHODS

A nested case-control study was performed in Osteoarthritis Initiative (OAI) participants: Cases with KR between 12 and 60 month (M) follow-up were each matched with one control (without KR through 60M) by age, sex, and baseline radiographic stage. Femoro-tibial cartilage thickness was measured quantitatively using magnetic resonance imaging (MRI) at the annual visit prior to KR occurrence (T0), and at 1-4 years prior to T0 (T-1 to T-4). Cartilage loss between cases and controls was compared using paired t-tests and conditional logistic regression.

RESULTS

One hundred and eighty-nine knees of 164 OAI participants [55% women; age 64 ± 8.7; body mass index (BMI) 29 ± 4.5] had KR and longitudinal cartilage data. Comparison of annualized slopes of change across all time points revealed greater loss in the central medial tibia (primary outcome) in KRs than in controls [94 ± 137 vs 55 ± 104 μm; P = 0.0017 (paired t); odds ratio (OR) 1.36 (95% confidence interval (CI): 1.08-1.70)]. The discrimination was stronger for T-2 → T0 [OR 1.61 (1.33-1.95), n = 127] than for T-1 → T0, and was not statistically significant for intervals prior to T-2 [i.e., T-4 → T-2, OR 0.97 (0.67-1.41), n = 60]. Results were similar for total medial femoro-tibial cartilage loss (secondary outcome), and when adjusting for pain and BMI.

CONCLUSIONS

In knees with subsequent replacement, cartilage loss accelerates in the 2 years, and particularly in the year prior to surgery, compared with controls. Whether slowing this cartilage loss can delay KR remains to be determined.

Imaging research results from the osteoarthritis initiative (OAI): a review and lessons learned 10 years after start of enrolment

The Osteoarthritis Initiative (OAI) is a multicentre, prospective, observational, cohort study of knee osteoarthritis (OA) that began recruitment in 2004. The OAI provides public access to clinical and image data, enabling researchers to examine risk factors/predictors and the natural history of knee OA incidence and progression, and the qualification of imaging and other biomarkers. In this narrative review, we report imaging findings and lessons learned 10 years after enrolment has started. A literature search for full text articles published from the OAI was performed up to 31 December 2013 using Pubmed and the OAI web page. We summarise the rationale, design and imaging protocol of the OAI, and the history of OAI publications. We review studies from early partial, and later full OAI public data releases. The latter are structured by imaging method and tissue, reviewing radiography and then MRI findings on cartilage morphology, cartilage lesions and composition (T2), bone, meniscus, muscle and adipose tissue. Finally, analyses directly comparing findings from MRI and radiography are summarised. Ten years after the first participants were enrolled and first papers published, the OAI has become an invaluable resource to the OA research community. It has fuelled novel methodological approaches of analysing images, and has provided a wealth of information on OA pathophysiology. Continued collection and public release of long-term observations will help imaging measures to gain scientific and regulatory acceptance as 'prognostic' or 'efficacy of intervention' biomarkers, potentially enabling shorter and more efficient clinical trials that can test structure-modifying therapeutic interventions (NCT00080171).