Minimum Medial Joint Space Width Research Articles

Radiographic measures of settlement phenomenon in patients with medial compartment knee osteoarthritis.

In this study, we proposed for the first time the theory of "settlement phenomenon" in tibial plateau and carefully explored the role of settlement of tibial plateau in the occurrence and progression of medial compartment knee osteoarthritis (OA) through investigating the relationship between the degree of settlement and the radiographic severity of OA. One hundred twenty-seven patients with knee medial compartment OA were recruited and examined with weight-bearing radiographs of the entire lower limb. The radiographic severity of OA was evaluated using the Kellgren and Lawrence (KL) grading methods. The settlement value, hip-knee-ankle angle, minimum medial joint space width, and condylar plateau angle were measured at the same time. The settlement value increases with the upgrading of KL grades (r = 0.352, P < 0.001) and is significantly correlated with the changes of hip-knee-ankle angle, minimum medial joint space width, and condylar plateau angle (r = -0.527, -0.271, and 0.415, P < 0.001, respectively). These results suggest that the settlement of tibial plateau could be an evaluable indicator of medial compartment knee OA and be used in the early diagnosis and progression of OA.

Longitudinal (One‐Year) Change in Cartilage Thickness in Knees With Early Knee Osteoarthritis: A Within‐Person Between‐Knee Comparison

Objective: To test the hypothesis that cartilage displays significant longitudinal thickening in the external subregions of the central medial (ecMF) and lateral (ecLF) femur in knees with early radiographic osteoarthritis (ROA) compared with contralateral knees without ROA, and to explore differences in change in other subregions and in radiographic joint space width (JSW). Methods: 50 participants (50% women; age 61.1±9.7y; BMI 27.7±4.7kg/m2 ) were identified from the Osteoarthritis Initiative cohort with definite femorotibial osteophytes but no JSN in one knee (early ROA), and no osteophytes or JSN in the contralateral knee (non-ROA). A longitudinal within-person, between-knee comparison was performed using measures of subregional cartilage thickness based on analyses of sagittal DESSwe MR images obtained at baseline and 1-year. Medial JSW was evaluated from fixed flexion radiographs. Results: The change between baseline and 1-year was -6±94µm in ecMF and +18±91µm in ecLF in early ROA (p=0.78) vs. -1±68µm and +4±76µm in non-ROA knees (p=0.38). The variability of cartilage thickness change tended to be greater in early ROA than in non-ROA knees. Greater cartilage thickness loss in the lateral tibia and a greater reduction in minimum medial JSW was observed in early ROA vs. non-ROA knees. Conclusion: There was no direct evidence of longitudinal cartilage thickening in external subregions of the central femur in knees with early ROA compared with contralateral non-ROA knees. The observed greater variability in longitudinal thickness change in early ROA knees (but not in non-ROA knees) might be due to cartilage thickening and thinning occurring simultaneously in these knees.

Radiographic subchondral bone trabecular integrity predicts osteoarthritis structural outcomes after anterior cruciate ligament rupture

Purpose: The course of post-traumatic osteoarthritis (OA) is an invaluable paradigm for discovery of markers of the very earliest stages of the OA disease process. Subchondral bone trabecular integrity (BTI) predicts structural progression of radiographic knee OA based on radiographic and MRI outcomes. The goal of this study was to determine if the BTI in a knee injury cohort, measured within 5 weeks after an anterior cruciate ligament (ACL) tear, is an early indicator of risk for development of OA over the subsequent 5 years. We hypothesized that thinning and loss of the subchondral vertical bone trabeculae, detected by BTI, would predict joint space width and joint space area loss. Methods: Bone trabecular integrity (BTI) of the medial tibial plateau was determined from analysis of knee radiographs from the completed randomized controlled KANON clinical trial (http://www.controlled-trials.com; ISRCTN 84752559), designed to compare rehabilitation plus early ACL reconstruction (ACLR, n = 61) versus rehabilitation plus optional delayed ACLR (n = 60) with follow-up out to 5 years. The KANON study enrolled 121 young active adults (aged 18–35 yrs) with acute ACL rupture within the prior 5 weeks to a previously uninjured knee. There was no loss to follow-up at 2 years and only 1 individual lost to follow-up at 5 years; none of the index knees had radiographic OA at baseline. Weight bearing knee radiographs, obtained at baseline (at time of enrollment), 2 years and 5 years using a modified Lyon-Schuss protocol, were analyzed using KneeAnalyzer software (Optasia Medical Ltd, Manchester, UK) to obtain fractal dimensions for computing BTI, minimum medial joint space width (mJSW), and medial joint space area (JSA). Multivariable regression models, adjusted for age, gender and body mass index, were used to evaluate the ability of baseline (BL) BTI parameters of index knees to predict the change in mJSW and JSA between BL and 2 y and 5 y after injury. Results: Based on BTI profiles injured knees on average showed thinning of vertical trabeculae over 2 years with further thinning between 2 and 5 years. Horizontal trabeculae showed thickening over 2 years with little further change to 5 years. Baseline BTI parameters were statistically significantly associated with change in mJSW over 2 (R2 0.19, p = 0.036) and 5 (R2 0.16, p = 0.04) years, and change in JSA over 5 (R2 0.22, p = 0.004), but not 2 (R2 0.13, p = 0.16) years. Conclusions: The qualitative changes in BTI parameters over time after injury, reflecting vertical and horizontal trabecular structure, were similar to changes earlier reported over similar time intervals in knee OA progressors. The remarkable finding that baseline BTI predicted subsequent changes in mJSW and JSA suggests that acute injury leads to dramatic acute alterations in bone structure, and/or, that pre-injury BTI identifies and perhaps contributes to, risk of knee injury. Longitudinal surveillance, initiated prior to injury, is needed to determine if BTI might identify individuals at high-risk for post-injury OA and who could be targeted with interventions to prevent subsequent development of OA.

Comparison of fixed flexion, fluoroscopic semi-flexed and MTP radiographic methods for obtaining the minimum medial joint space width of the knee in longitudinal osteoarthritis trials

To compare three radiographic techniques (fluoroscopic semi-flexed [Fluoro], fixed flexion [FF], and semi-flexed metatarsophalangeal joint [MTP] views) for measuring medial joint space width (JSW) of the knee in longitudinal osteoarthritis (OA) trials and to identify the percentage of patients with detectable progression. Retrospective summary of the progression and variability of the change in JSW in knee OA. Data from the placebo arms of three separate, structure modifying, knee OA trials were compared including gender, age, baseline JSW, change from baseline in JSW, duration of observation, and number and percent of patients with joint space narrowing of various degrees. Computer evaluation of the joint space at its narrowest point in the medial compartment was used in the studies. It is important to note that the narrowest joint space at baseline may not be in the same anatomic location at subsequent evaluations. No statistical tests were performed. The average observation times were 0.98, 0.68 and 0.82 years for the Fluoro, FF, and MTP studies, respectively. The amount of progression was different among the three studies. The Fluoro study showed the greatest magnitude of OA structural progression and the lowest variability. The Fluoro study was expected to show the greatest magnitude of structural progression since it was conducted for the longest duration. For all patients, the standard deviation of the change in JSW was 0.42, 0.63, and 0.53 mm for the Fluoro, FF, and MTP studies, respectively. The percent of patients with detectable progression was similar across studies. With these data, information was not sufficient to control for duration of observation and differences in inclusion criteria for the three study populations. Therefore, no definitive conclusions can be made regarding the degree of progression of OA over specific time intervals. However, the data indicate that all three studies contain a cohort of patients that exhibit detectable progression.

Cancellous bone differences between knees with early, definite and advanced joint space loss; a comparative quantitative macroradiographic study

To quantify differences in bone structure in the proximal tibia of patients with mild, definite and advanced osteoarthritis (OA) compared to healthy reference tibiae. Patients with medial compartment OA (n=110; F=70), mean+/-SD age 61.0+/-10.2 years, and non-OA reference subjects (n = 27; F = 10) mean+/-SD age 36.3+/-11.4 years had 4x macroradiographs digitised by laser scanner. Computer measurement of minimum medial joint space width (JSW) subdivided available OA knees into those with early (JSW > 3 mm, n=70), definite (JSW </= 3 > 1.5 mm, n = 52) and advanced OA (JSW </= 1.5 mm, n = 60). Non-OA knees (n = 49) had JSW > 4.5 mm. Fractal Signature Analysis (FSA), a computerised image analysis technique, measured differences in cancellous bone structure between OA and non-OA tibiae at four regions of interest (ROIs). Compared to non-OA, FSA of vertical trabeculae increased significantly (P < 0.05) at most sizes (0.12-1.14 mm) in all OA subgroups and ROIs, with greatest increase occurring in the medial diseased compartment. Compared to early OA, FSA of vertical trabeculae increased significantly (P<0.05) at most sizes (0.36-1.14 mm) in subchondral and subarticular ROIs in definite and advanced OA. Compared to non-OA, FSA of horizontal trabeculae increased significantly (P < 0.05) at some small sizes in all ROIs and OA subgroups, and decreased significantly (P<0.05) at large sized horizontal trabeculae (0.60-1.14 mm) in the medial subarticular region in advanced OA. The increase in FSA (consistent with increased trabecular number associated with thinning and fenestration in regions of dense cancellous bone) of most vertical and some horizontal trabeculae confirms that cancellous bone within the proximal tibia of OA patients is osteoporotic.