Similar patient reported outcomes at long-term follow-up after external fixation versus internal fixation of the anterior ring component of APC injuries.

PURPOSE: Unstable pelvic ring injuries produced by external rotation of the hemipelvis and a symphyseal disruption are most often treated with internal fixation of the anterior ring, with percutaneous treatment of the posterior ring as needed. In some clinical situations, patients are treated with external fixation for their anterior injuries and the long-term functional outcomes associated with external fixation are not well understood. We ask if there is a difference in functional outcome, between treatment of these injuries with internal versus external fixation, when measured at a minimum of three years after injury. METHOD: This was a retrospective cohort study performed at a level one regional trauma center. Trauma database review identified 128 patients, with 70 subsequently excluded, with unstable anterior posterior compression (APC) pelvic ring injuries (OTA 61B2.3 & 61C1.2) treated with surgery with minimum three years of follow-up. An intervention of internal fixation versus external fixation of anterior pelvic ring was performed, and depending on the injury, supplemented with posterior iliosacral screw fixation. Main outcome was measured with the Majeed functional outcome score (0-100). RESULTS: Patients treated with external fixation reported a Majeed score of 70 (95% CI 28-100) compared to 79 (95% CI 36-100) in those with internal fixation (p-value 0.28). Subgroups of the Majeed score were not significantly different (p value > 0.05). Open fractures, severity of injury, and ISS were worse in those treated with external fixation. There was no differential loss to follow-up. Conclusion Patients with unstable pelvic ring injuries with symphyseal disruptions treated with external fixation as definitive treatment versus internal fixation may fare no different in the long term.

Does Coronal Plane Malalignment of the Tibial Insert in Total Ankle Arthroplasty Alter Distal Foot Bone Mechanics? A Cadaveric Gait Study.

BACKGROUND: Total ankle arthroplasty (TAA) is becoming a more prevalent treatment for end-stage ankle arthritis. However, the effects of malalignment on TAA remain poorly understood. QUESTIONS/PURPOSES: The purpose of this study was to quantify the mechanical effects of coronal plane malalignment of the tibial insert in TAA using cadaveric gait simulation. Specifically, we asked, is there a change in (1) ankle joint congruency, (2) kinematic joint position, (3) kinematic ROM, (4) peak plantar pressure, and (5) center of pressure with varus and valgus malalignment? METHODS: A modified TAA was implanted into seven cadaveric foot specimens. Wedges were used to simulate coronal plane malalignment of the tibial insert. The degree of malalignment (tibial insert angle [TIA] and talar component angle [TCA]) was quantified radiographically for neutral and 5°, 10°, and 15° varus and valgus wedges. Dynamic walking at 1/6 of physiological speed was simulated using a robotic gait simulator. A motion capture system was used to measure foot kinematics, and a pressure mat was used to measure plantar pressure. Joint congruency was quantified as the difference between TIA and TCA. Continuous joint position, joint ROM, peak plantar pressure, and center of pressure for varus and valgus malalignment compared with neutral alignment were estimated using linear mixed effects regression. Pairwise comparisons between malalignment conditions and neutral were considered significant if both the omnibus test for the overall association between outcome and malalignment and the individual pairwise comparison (adjusted for multiple comparisons within a given outcome) had p ≤ 0.05. RESULTS: Descriptively, the TIA and TCA were both less pronounced than the wedge angle and component incongruence was seen (R = 0.65; p < 0.001). Varus malalignment of the tibial insert shifted the tibiotalar joint into varus and internally rotated the joint. The tibiotalar joint's ROM slightly increased as the TIA shifted into varus (1.3 ± 0.7° [mean ± SD] [95% confidence interval -0.7 to 3.4]; p = 0.03), and the first metatarsophalangeal joint's ROM decreased as the TIA shifted into varus (-1.9 ± 0.9° [95% CI -5.6 to 1.7]; p = 0.007). In the sagittal plane, the naviculocuneiform joint's ROM slightly decreased as the TIA shifted into varus (-0.9 ± 0.4° [95% CI -2.1 to 0.3]; p = 0.017). Hallux pressure increased as the TIA became more valgus (59 ± 50 kPa [95% CI -88 to 207]; p = 0.006). The peak plantar pressure slightly decreased in the third and fourth metatarsals as the TIA shifted into valgus (-15 ± 17° [95% CI -65 to 37]; p = 0.03 and -8 ± 4° [95% CI -17 to 1]; p = 0.048, respectively). The fifth metatarsal's pressure slightly decreased as the TIA shifted into valgus (-18 ± 12 kPa [95% CI -51 to 15]) or varus (-7 ± 18 kPa [95% CI -58 to 45]; p = 0.002). All comparisons were made to the neutral condition. CONCLUSIONS: In this cadaver study, coronal plane malalignment in TAA altered foot kinematics and plantar pressure. In general, varus TAA malalignment led to varus shift and internal rotation of the tibiotalar joint, a slight increase in the tibiotalar ROM, and a slight decrease in the first metatarsophalangeal ROM, while a valgus TAA malalignment was manifested primarily through increased hallux pressure with a slight off-loading of the third and fourth metatarsals. CLINICAL RELEVANCE: This study may increase our understanding of the biomechanical processes that underlie the unfavorable clinical outcomes (such as, poor patient-reported outcomes or implant loosening) that have been associated with coronal plane malalignment of the tibial component in TAA.

A Teachable Moment After Orthopaedic Fracture in the Smoking Patient: A Randomized, Controlled Trial.

OBJECTIVES: To assess whether education during hospitalization after an acute fracture changes patient attitudes toward smoking-related complications and to assess whether this change persists into the first outpatient follow-up visit. DESIGN: Prospective, randomized, controlled trial. SETTING: Level 1 trauma center. PATIENTS: Inpatients with fractures who identified as smokers: 40 assessed for inclusion and randomized, 30 completed inpatient assessments, and 20 completed outpatient follow-up. INTERVENTION: An educational intervention by the researcher to teach the patient about the harms of smoking regarding fracture healing. MAIN OUTCOME MEASURES: A novel questionnaire to assess the intervention via Likert scale responses, evaluating perceived risk, affective response, and self-role. RESULTS: Education resulted in an increase in perceived risk and affective response within the cohort and an increase in perceived risk when compared with control subjects. No significant differences persisted into outpatient follow-up. CONCLUSIONS: This trial demonstrated that a teachable moment can have an early effect on certain attitudes toward smoking after an acute fracture. These changes did not persist at the first follow-up visit. LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Postnatal progression of bone disease in the cervical spines of mucopolysaccharidosis I dogs.

INTRODUCTION: Mucopolysaccharidosis I (MPS I) is a lysosomal storage disorder characterized by deficient α-l-iduronidase activity leading to accumulation of poorly degraded dermatan and heparan sulfate glycosaminoglycans (GAGs). MPS I is associated with significant cervical spine disease, including vertebral dysplasia, odontoid hypoplasia, and accelerated disk degeneration, leading to spinal cord compression and kypho-scoliosis. The objective of this study was to establish the nature and rate of progression of cervical vertebral bone disease in MPS I using a canine model. METHODS: C2 vertebrae were obtained post-mortem from normal and MPS I dogs at 3, 6 and 12 months-of-age. Morphometric parameters and mineral density for the vertebral trabecular bone and odontoid process were determined using micro-computed tomography. Vertebrae were then processed for paraffin histology, and cartilage area in both the vertebral epiphyses and odontoid process were quantified. RESULTS: Vertebral bodies of MPS I dogs had lower trabecular bone volume/total volume (BV/TV), trabecular thickness (Tb.Th), trabecular number (Tb.N) and bone mineral density (BMD) than normals at all ages. For MPS I dogs, BV/TV, Tb.Th and BMD plateaued after 6 months-of-age. The odontoid process appeared morphologically abnormal for MPS I dogs at 6 and 12 months-of-age, although BV/TV and BMD were not significantly different from normals. MPS I dogs had significantly more cartilage in the vertebral epiphyses at both 3 and 6 months-of-age. At 12 months-of-age, epiphyseal growth plates in normal dogs were absent, but in MPS I dogs they persisted. CONCLUSIONS: In this study we report reduced trabecular bone content and mineralization, and delayed cartilage to bone conversion in MPS I dogs from 3 months-of-age, which may increase vertebral fracture risk and contribute to progressive deformity. The abnormalities of the odontoid process we describe likely contribute to increased incidence of atlanto-axial subluxation observed clinically. Therapeutic strategies that enhance bone formation may decrease incidence of spine disease in MPS I patients.