Steven M. Cherney

In Vivo Syndesmotic Overcompression After Fixation of Ankle Fractures With a Syndesmotic Injury.

Objectives: The goals of this study were to assess syndesmotic reductions using computerized tomography and to determine whether malreductions are associated with certain injury types or reduction forceps. Design: Prospective cohort. Setting: Urban level 1 trauma center. Patients: Twenty-seven patients with operatively treated syndesmotic injuries were recruited prospectively. Intervention: Patients underwent postoperative bilateral computerized tomography of the ankle and hindfoot to assess syndesmotic reduction. The uninjured extremity was used as a control. Main outcome measurement: Side-to-side differences of the fibular position within the tibial incisura were measured at several anatomic points and analyzed based on injury type, the presence of posterior malleolar injury, level of fracture, and type of reduction forceps used. Results: On average, operatively treated syndesmotic injuries were overcompressed (fibular medialization) by 1 mm (P < 0.001) and externally rotated by 5° (P = 0.002) when compared with the uninjured extremity. The absence of a posterior malleolar injury and Weber B (OTA 44-B) fractures seemed to have a protective effect against malrotation, but not against overcompression. There was no difference in malreduction based on the type of the clamp used. Conclusions: It is possible, and highly likely based on these data, to overcompress the syndesmosis when using reduction forceps. Care should be taken to avoid overcompression, as this may affect the ankle motion and functional outcomes. To our knowledge, this is the first in vivo series of syndesmotic overcompression. Level of Evidence: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Biomechanical Considerations for Surgical Stabilization of Osteoporotic Fractures

The incidence of osteoporotic fractures has been steadily rising along with the aging of the population. Surgical management of these fractures can be a challenge to orthopedic surgeons. Diminished bone mass and frequent comminution make fixation difficult. Advancements in implant design and fixation techniques have served to address these challenges and when properly applied, can improve overall outcome. The purpose of this review is to describe fixation challenges of common osteoporotic fractures and provide options for successful treatment.

Incisura Morphology as a Risk Factor for Syndesmotic Malreduction

Background: The goal of this study was to objectively assess if rotational or translational syndesmotic malreduction is associated with certain syndesmotic morphologies. Prior studies based on subjective assessment of syndesmotic morphology and reduction have not shown any difference between groups. Methods: Thirty-five prospectively recruited patients with operatively treated syndesmotic injuries were recruited at an Urban Level I Trauma Center. Patients underwent postoperative bilateral computed tomographic (CT) scans of the ankle to assess incisura depth and syndesmotic reduction. The uninjured extremity was used as a control. Side-to-side differences of syndesmotic reduction were measured at several anatomic points and compared to the incisura depth. Results: There was a significant correlation between more shallow syndesmoses and increased anterior translation of the fibula in the incisura (r = −0.63, P ≤ .001). Six of 8 patients with “shallow” (≤2.5 mm) incisura were anteriorly malreduced greater than or equal to 1.5 mm compared to the contralateral ankle. The anterior malreduction rate in those with a shallow incisura was significantly greater than in the “non-shallow” patients (P < .001). There were 9 patients with incisurae greater than or equal to 4.5 mm deep. Five of the “deep” patients had posterior malreductions greater than or equal to 1.5 mm. The posterior malreduction rate in the “deep” group was significantly greater than the “non-deep” patients (P = .02). There was a significant correlation between increasing syndesmotic depth and increased malrotation (r = .46, P = .01). Conclusion: Syndesmotic morphology was found to be associated with specific malreduction patterns. Shallow syndesmoses were correlated with anterior fibular malreduction, and were less likely to be malrotated. Conversely, deep syndesmoses predisposed to posterior sagittal plane and rotational malalignment. Preoperative CT scans that assess the syndesmosis morphology may allow surgeons to alter reduction strategies to avoid syndesmotic malreduction. Level of Evidence: Level III, retrospective cohort study.

Increased Reduction Clamp Force Associated With Syndesmotic Overcompression

Background: The distal tibiofibular syndesmosis is disrupted in up to 45% of operatively treated ankle fractures, and syndesmotic malreduction has historically been correlated with poor outcome. The purpose of this study was to quantify the clamp force used during syndesmotic reduction and to evaluate the effect of clamp force on fibular overmedialization (overcompression) at the level of the distal tibiofibular syndesmosis. Methods: A prospectively recruited cohort of 21 patients underwent operative syndesmotic reduction and fixation. A ball point periarticular reduction forceps that was modified to include a load cell in one tine was used for the reduction, and the clamp force required for reduction was measured. Patients underwent postoperative bilateral computed tomographic scans of the ankle and hindfoot to assess syndesmotic reduction. The uninjured extremity was used as a control. Side-to-side differences in fibular medialization, translation, and rotation within the tibial incisura were measured. These findings were correlated with the reduction clamp force utilized to obtain the reduction. Results: Syndesmotic overcompression (fibular medialization greater than 1.0 mm when compared with noninjured ankle) was seen in 11 of 21 patients (52%). Increased clamp force significantly correlated with syndesmotic overcompression. The mean reduction clamp forces were 88 N for the undercompressed group, 130 N for the adequately compressed group, and 163 N for the overcompressed group. Conclusion: This study demonstrated a significant correlation between increased clamp forces and syndesmotic overcompression, and determined objective forces that lead to overcompression. Our results indicate that surgeons should be cognizant of the clamp force used for syndesmotic reduction. Level of Evidence: Level III, case-control series, in accordance with STROBE guidelines.

Trapeziometacarpal Arthritis: A Prospective Clinical Evaluation of the Thumb Adduction and Extension Provocative Tests.

PURPOSE To determine the diagnostic performance (ie, sensitivity, specificity, interrater reliability) of the thumb metacarpal adduction and extension tests against traditional examination maneuvers for trapeziometacarpal (TMC) arthritis. METHODS This cross-sectional study recruited 129 patients from 2 outpatient offices at a tertiary institution. All patients had radiographic wrist examinations and completed a standardized physical examination consisting of the thumb adduction and extension tests as well as standard examination maneuvers for radial wrist and thumb pain. The physical examinations were performed by 1 of 2 attending physicians and an independent examiner. Patients were recruited for 3 diagnostic groups: TMC arthritis, radial wrist or hand pain, and nonradial wrist pain controls. Statistical analysis calculated the sensitivity, specificity, and interrater reliability of each physical examination maneuver for detecting TMC arthritis. RESULTS The thumb adduction maneuver was found to have a sensitivity of 0.94 (confidence interval [CI], 0.82-0.98) and a specificity of 0.93 (CI, 0.86-0.97). The thumb extension maneuver had a sensitivity of 0.94 (CI, 0.82-0.98) and a specificity of 0.95 (CI, 0.87-0.98). The interrater reliability was excellent for both the adduction (κ = 0.79) and the extension tests (κ = 0.84). The grind test had a sensitivity of 0.44 (CI, 0.30-0.59), a specificity of 0.92 (CI, 0.84-0.97), and poor interrater reliability (0.31). Point tenderness at the TMC joint had a sensitivity of 0.94 (CI, 0.82-0.98), a specificity of 0.81 (CI, 0.71-0.88) and fair interrater reliability (κ = 0.63). CONCLUSIONS The adduction and extension tests each proved to be more sensitive than the grind test for the detection of TMC arthritis. Further, these provocative tests were more specific for basal joint arthrosis than was the elicitation of point tenderness at the joint. The metacarpal adduction and extension maneuvers demonstrated excellent utility as screening tests for the identification of TMC arthritis. TYPE OF STUDY/LEVEL OF EVIDENCE Diagnostic II.

Informed Consent to Research with Cognitively Impaired Adults: Transdisciplinary Challenges and Opportunities

ABSTRACT Due to issues related to informed research consent, older adults with cognitive impairments are often excluded from high-quality studies that are not directly related to cognitive impairment, which has led to a dearth of evidence for this population. The challenges to including cognitively impaired older adults in research and the implications of their exclusion are a transdisciplinary issue. The ethical challenges and logistical barriers to conducting research with cognitively impaired older adults are addressed from the perspectives of three different fields—social work, emergency medicine, and orthopaedic surgery. Issues related to funding, study design, intervention components, and outcomes are discussed through the unique experiences of three different providers. A fourth perspective—medical research ethics—provides alternatives to exclusion when conducting research with cognitively impaired older adults such as timing, corrective feedback and plain language, and capacity assessment and proxy appointments. Given the increasing aging population and the lack of evidence on cognitively impaired older adults, it is critical that researchers, funders, and institutional review boards not be dissuaded from including this population in research studies.

Bicondylar tibial plateau fractures: assessing and treating the medial fragment.

Successful treatment of bicondylar tibial plateau requires focused and specific assessment and treatment of the medial fragment. Many fragment variations exist that help guide treatment. This may include posteromedial or medial plating using a variety of reduction and fixation techniques, or indirect reduction and lateral locked plating. With appropriate assessment, good results can be achieved.

Surgical approaches to intramedullary nailing of the tibia: Comparative analysis of knee pain and functional outcomes

INTRODUCTION Post-operative knee pain is common following intramedullary nailing of the tibia, regardless of surgical approach, though the exact source is controversial. Historically, the most common surgical approaches position the knee in hyperflexion, including patellar tendon splitting (PTS) and medial parapatellar (MPP). A novel technique, the semi-extended lateral parapatellar approach simplifies patient positioning, fracture reduction, fluoroscopic assessment, and implant insertion. It also avoids violation of the knee joint capsule. However, this approach has not yet been directly compared against the historical standards. We hypothesised that in a comparison of patient outcomes, the semi-extended approach would be associated with decreased knee pain and better function relative to knee hyperflexion approaches. METHODS A trauma patient database from a Level I centre was queried for patients who underwent intramedullary nailing of the tibia between 2009 and 2013. Patients were surveyed for knee pain severity (NRS scale 1 to 10) and location, and completion of the Lysholm Knee Scale (LKS). Data was compared between the semi-extended lateral parapatellar, medial parapatellar, and tendon splitting groups regarding knee pain severity, location, total LKS, and individual knee function scores from the Lysholm questionnaire. Pre-hoc power analysis determined the necessary sample size (n=34). Post-hoc analysis utilised two-way ANOVA analysis with a significance threshold of p<0.05. RESULTS Comparison of knee pain severity between the groups found no significant difference (p=0.69), with average ratings of: semi-extended (3.26), PTS (3.59), and MPP (3.63). Analysis found no significant differences in total LKS score (p=0.33), with average sums of: semi-extended (75.97), MPP (77.53), and PTS (81.68). Individual knee function scores from the LKS were similar between the groups, except for limping, with MPP being significantly worse (p=0.04). There was no significant difference in knee pain location (p=0.45). CONCLUSION In this adequately-powered study, at minimum 1 year follow-up there were no significant differences between the 3 approaches in knee pain severity, location, or overall function. The three were significantly different in post-operative limping, with medial parapatellar having the lowest score. The semi-extended lateral parapatellar approach vastly simplifies many technical aspects of nailing compared to knee hyperflexion approaches, and does not violate the knee joint.

Technical Causes of ACL Graft Failure

Revision anterior cruciate ligament reconstruction has a higher failure rate and worse clinical outcomes than primary reconstruction. A number of technical factors can contribute to these results. Proper tunnel positioning on the femoral and tibial sides is critically important, and tunnel malposition is the most common technical cause of graft failure. Recognizing tunnel enlargement and properly preparing the tunnels are likewise important. Graft-related factors that may contribute to failure include improper graft choice, as well as inadequate graft fixation or tensioning. Failure to address limb malalignment and concomitant ligamentous injuries may also contribute to ACL graft failure. Errors in notchplasty can lead to graft failure, as well. Each of these factors should be addressed in the planning and execution of revision ACL reconstructions.

Joint Space Loss after Arthroscopic Partial Meniscectomy: Data from the Osteoarthritis Initiative

Objectives: Knee osteoarthritis (OA) is a prevalent disease that causes substantial disability and use of medical resources, and knee arthroscopy is frequently performed in patients with OA or at risk of developing OA. While meniscectomy has been associated with progression of OA in multiple studies, none have assessed progression of joint space width (JSW) loss compared to matched controls. The Osteoarthritis Initiative (OAI) provides a unique cohort to enable this evaluation. We hypothesize that JSW significantly decreases in meniscectomy patients versus matched controls within a one-year period, and that joint space loss continues to be more rapid in subsequent years. Methods: A prospective cohort study with matching was conducted using records from the OAI public use data sets. The cohort (n=4796) is contains the incidence subcohort (normal radiographs with risk of developing OA) and the progression subcohort (radiographic evidence of OA). Subjects have fixed-flexion radiographs taken at yearly intervals and validated measurements of JSW are performed. Additional details about the OAI and study design are publicly accessible at http://oai.epi-ucsf.org/datarelease/About.asp. 141 meniscectomy knees were identified and 141 controls were randomly selected while matching for subcohort, gender, study site, age, knee side, and year. Paired t-test was used to evaluate change in JSW over the first year in the 141 matched pairs. Repeated measures MANOVA with adjustment for age, gender, race, and BMI was used to assess longitudinal changes in JSW in a subset of 33 matched pairs with 4 years of JSW measurements available. Results: Meniscectomy and control groups were balanced with respect to age, gender, race, BMI, and baseline JSW. The JSW decrease overa 1-year period was 0.948 mm in meniscectomy knees and 0.137 mm in controls p<0.0001). Table 1 shows similar results when stratifying by subcohort. In the crude and adjusted analyses of knees with 4 years of follow-up, the rate of JSW loss after the first year was not significantly different between meniscectomy knees and controls as shown in Figure 1. Conclusion: Arthroscopic partial meniscectomy is associated with increased loss of JSW during the first year after surgery in knees with OA and knees at risk of developing OA; however, the rate of JSW loss is not accelerated over the next 3 years. Immediate JSW narrowing may occur due to loss of the interposed meniscus, due to morphologic changes such as flattening and extrusion, or due to rapid degeneration of articular cartilage in response to increased tibiofemoral contact stress. Significance among both subcohorts suggests that meniscectomy causes progression of osteoarthritis independent of disease stage. Future investigation of change in cartilage and meniscal volumes on MR imaging may further explain the cause of this joint space loss.