Reliability of new radiographic measurement techniques for elbow bony impingement

Background Identifying the location and scale of radiographic changes in elbow bony impingement (EBI) is critical in formulating an appropriate diagnosis and treatment plan for such patients. The purpose of present study was to evaluate the intra-rater and inter-rater reliability of the new radiographic parameters, Anterior Impingement angle (AIa) and Posterior Impingement angle (PIa), for EBI. In addition, to determine if there was a relationship between radiographic parameters and clinical evaluation. Patients and methods Three raters of different levels of training evaluated the radiographs of 60 patients (30 in EBI group and 30 in normal group) twice, at least 2 weeks apart. Intra-rater and inter-rater reliabilities were calculated by Intraclass Correlation Coefficients (ICC) with 95% confidence intervals. Correlation between radiographic parameters and clinical evaluation was calculated by Pearson correlation coefficient. Results In both groups, intra-rater and inter-rater reliabilities were substantial. There were no significant differences in reliability between upper-hand expert surgeons and resident for either measurement. Good correlation was observed between impingement arcs and range of motion values. Conclusions Both AIa and PIa measurements demonstrated substantial intra-rater and inter-rater reliability for normal radiographs and in EBI patients. Good reliability, for either expert surgeons or residents in training, and good correlation between radiographic measurements and manual testing, appoints this method may be easily and reliably used in every day practice.

Relationship between talofibular impingement and increased talar tilt in incongruent varus ankle osteoarthritis

Purpose This study aimed to evaluate the relationship between talofibular impingement and increased talar tilt in incongruent varus ankle osteoarthritis. Methods: Incongruent varus ankle osteoarthritis was defined as a talar tilt of more than 4° on standard ankle anteroposterior radiographs. We retrospectively reviewed 30 patients with unilateral incongruent varus ankle osteoarthritis with normal alignment of the contralateral ankle. All patients underwent bilateral weightbearing computed tomography and standing plain radiographs. The talar tilt and the distance between the talar lateral process and lateral malleolar tip were measured from a standing ankle anteroposterior radiograph of both sides. Talar and fibular spurs were assessed on the coronal and axial views of weightbearing computed tomography. After simulating the correction of the talar tilt in varus ankle osteoarthritis, talofibular bony impingement was reassessed. Results: On the varus side, the distance between the talar lateral process and the lateral malleolar tip was significantly shorter than that on the contralateral side ( p < .001). Talar spur was present in the varus side of all 30 patients on the axial view of weightbearing computed tomography and in the control side of 10 patients. After the simulation of talar tilt correction, talofibular impingement (overlap) occurred in all 30 patients with a larger extent in the severe talar tilt subgroup ( p < .001). Conclusion: Talofibular impingement by lateral gutter osteophytes is closely related to increased talar tilt in patients with incongruent varus ankle osteoarthritis. Therefore, lateral gutter osteophytes should be resected to stabilize mortise and improve clinical outcomes.

Arthroscopic treatment of anteromedial ankle impingement

Objective: Impingement syndromes are recognized as an important cause of chronic ankle pain, which results from the entrapment of an inflamed soft-tissue component between the osteophytes. The predominant site of occurrence is the anterolateral aspect of the ankle for soft-tissue impingement, and anteromedial aspect for bony impingement. Symptoms related to the physical impact of bone or soft-tissue pain often result in limited ankle range of motion. Methods: We conducted a retrospective study of 34 patients (34 ankles) with anteromedial bony impingement. All patients underwent arthroscopy, with a mean follow-up of 34 months. Results: All osteophytes were removed, and the ankle range of motion improved. The AOFAS score improved from 73 preoperatively to 95 postoperatively. Conclusion: The arthroscopic removal of the anteromedial osteophytes of the ankle had excellent functional results. It is an effective procedure that allows rapid patient recovery. Level of Evidence IV; Therapeutic Studies; Case Series.

High Offset Stems are Protective of Dislocation in High Risk Total Hip Arthroplasty

Background: Spinal stiffness has been shown to increase risk of dislocation due to impingement and instability. Increasing anteversion of the acetabular component has been suggested to prevent dislocation, but little has been discussed in terms of femoral or global offset restoration. The purpose of this study is to quantify dislocation rates after primary THA using standard versus high offset femoral components and to determine how differences in offset affect impingement-free range of motion in a stiff spine cohort using a novel impingement model. Methods: 12,365 patients undergoing THA from 2016-2018 were retrospectively reviewed to determine dislocation rates and utilization of standard versus high offset stems. For 50 consecutive patients with spinal stiffness, a CT-based computer software impingement modeling system assessed bony or prosthetic impingement during simulated range of motion. The model was run 5 times for each patient with varying offsets. Range of motion was simulated in each scenario to determine the degree at which impingement occurred. Results: There were 51 dislocations for a 0.41% dislocation rate. Total utilization of high offset stems in the entire cohort was 49%. Of those patients who sustained a dislocation, 49 (96%) utilized a standard offset stem. The impingement modeling demonstrated 5 degrees of added range of motion until impingement for every 1mm offset increase. Conclusion: In the impingement model, high offset stems facilitated greater ROM before bony impingement and resulted in lower dislocation rates. In the setting of high-risk THA due to spinal stiffness, surgeons should consider the use of high-offset stems and pay attention to offset restoration.

Post-operative Virtual Range of Motion in Robotic-assisted THA Patients to determine Pre-operative Simulation Needs

For preoperative simulations of hip range of motion to be useful in predicting complications after total hip arthroplasty (THA), the factors that could affect post-operative function must be considered including, but not limited to, bony impingement, pelvic position, and implanted vs. planned differences. This study retrospectively simulates ranges of motion to prosthetic and bony impingement of THA patients with known planned and implanted component positions and pelvic tilt to determine the factors and needs to accurately simulate range of motion preoperatively.Twenty-two (22) anterolateral, cementless total hip arthroplasties were performed using robotic-arm assisted technology which allowed capture of the implanted stem version and position in addition to robotic-assisted cup placement to plan. With the known implanted positions and preoperative 3-dimentional (3D) bone models, six (6) hip maneuvers were virtually simulated in custom software. Correlations were evaluated between planned and implanted component positions, pelvic tilt, ranges of motion, and patient-reported outcomes.Average ranges of motion to impingement were similar to those of previous simulation and navigation studies. Supine tilt varied from -10 ̊ (posterior) to 15 ̊ (anterior) with an average of 3.4±6.6 ̊. Very little correlation was seen between native or planned stem version and implanted stem version. Correlations were seen between some maneuvers such as internal rotation (IR) at 90 degrees flexion (F) (IR@90F) and combined component version and pelvic tilt. Bony impingement occurred during IR@90F in 9 of the 22cases. Pelvic tilt assessment, bony impingement detection, better prediction of implanted component position or the ability to execute a plan, such as robotically, would all provide a more accurate pre-operative simulation of the post-operative patient’s function.

Risk Factors for Osteochondral Lesions and Osteophytes in Chronic Lateral Ankle Instability: A Case Series of 1169 Patients

Background: Osteochondral lesions (OCLs) and bony impingement are common secondary lesions of chronic lateral ankle instability (CLAI), but the risk factors that predict OCLs and bony impingement are unknown. Purpose: To analyze the risk factors for the development of OCLs and osteophytes in patients with CLAI. Study Design: Case-control study; Level of evidence, 3. Methods: Patients diagnosed with CLAI at our institution from June 2007 to May 2018 were enrolled. The assessed potential risk factors were age, sex, postinjury duration, body mass index, injury side, and ligament injury type (isolated anterior talofibular ligament [ATFL] injury, isolated calcaneofibular ligament [CFL] injury, or concomitant ATFL and CFL injuries). Univariate and multivariate logistic regression analyses were performed to evaluate the association between these factors and the presence of OCLs and osteophytes. Results: A total of 1169 patients with CLAI were included; 436 patients (37%) had OCLs and 334 (31%) had osteophytes. The presence of OCLs was significantly associated with the presence of osteophytes ( P < .001). Male sex and older age were significantly associated with the presence of OCLs in the medial and lateral talus. A postinjury duration of 5 years or longer was significantly associated with the presence of OCLs in the medial talus (odds ratio [OR], 1.532; 95% CI, 1.023-2.293; P = .038) but not in the lateral talus. ATFL and CFL injuries were both significantly associated with the presence of lateral OCLs. Risk factors for the presence of osteophytes were male sex, older age, postinjury duration 5 years or longer, and CFL injury. Patients with concomitant ATFL and CFL injuries were significantly more likely to have osteophytes than were patients with single-ligament injuries ( P = .018). Conclusion: Risk factors for OCLs and osteophytes were postinjury duration of 5 years or longer, older age, and male sex. ATFL injury was associated with the presence of lateral OCLs, whereas CFL injury was associated with the presence of lateral OCLs and osteophytes. Patients with these risk factors should be closely monitored and treated to reduce the incidence of ankle arthritis.