Anterolateral Drawer Versus Anterior Drawer Test for Ankle Instability: A Biomechanical Model.

BACKGROUND: The addition of unconstrained internal rotation to the physical examination could allow for detection of more subtle degrees of ankle instability. We hypothesized that a simulated anterolateral drawer test allowing unconstrained internal rotation of the ankle would provoke greater displacement of the lateral talus in the mortise versus the anterior drawer test. METHODS: Ten cadaveric lower extremities were tested in a custom apparatus designed to reproduce the anterior drawer test and the anterolateral drawer test, in which the ankle was allowed to internally rotate about the intact deep deltoid ligament while being subluxed anteriorly. Specimens were tested intact and with anterior tibiofibular ligament sectioned. A differential variable reluctance transducer was used to measure lateral talar displacement with anterior forces of 25 and 50 N. RESULTS: No significant differences in talar displacement or ankle rotation were noted in intact specimens between the groups. Among sectioned specimens, significantly more talar displacement (25 N [6.5 ± 1.7 mm vs 3.8 ± 2.4 mm] and 50 N [8.7 ± 0.9 mm vs 4.5 ± 2.5 mm], P < .001) and ankle rotation (25 N [13.9 ± 8.0 degrees vs 0.0 ± 0.0 degrees] and 50 N [23.7 ± 5.8 degrees vs 0.0 ± 0.0 degrees], P < .001) were found in the anterolateral drawer versus anterior drawer group. CONCLUSION: In an ankle instability model, the anterolateral drawer test provoked almost twice the lateral talus displacement found with the anterior drawer test. CLINICAL RELEVANCE: Allowing internal rotation of the ankle while testing for ankle instability may allow the examiner to detect more subtle degrees of ankle instability.

Community-acquired Methicillin-resistant Staphylococcus aureus Musculoskeletal Infections: Emerging Trends Over the Past Decade.

BACKGROUND: The emergence of community-acquired methicillin-resistant Staphylococcus aureus (MRSA) has altered the management of pediatric musculoskeletal infections. Yet, institution-to-institution differences in MRSA virulence may exist, suggesting a need to carefully examine local epidemiological characteristics. The purpose of this study was to compare MRSA and methicillin-sensitive S. aureus (MSSA) musculoskeletal infections with respect to prevalence and complexity of clinical care over the past decade at a single children's hospital. METHODS: We retrospectively reviewed a series of patients presenting to The Children's Hospital of Philadelphia with a diagnosis of osteomyelitis, septic arthritis, or both over a 10-year period. Inclusion criteria were S. aureus (SA) infections proven by positive culture of blood, bone, or joint aspirate. Exclusion criteria were non-SA infectious etiologies. Hospital-acquired infections were also not included to exclusively evaluate acute, community-acquired cases. Data related to hospital course, laboratory values, and number of surgical interventions were collected and compared between MRSA and MSSA cohorts. RESULTS: In our series of pediatric patients, we identified 148 cases of acute, community-acquired musculoskeletal SA infections (MRSA, n=37 and MSSA, n=111). The prevalence of MRSA musculoskeletal infections increased from 11.8% in 2001 to 2002 to 34.8% in 2009 to 2010. Compared with MSSA, MRSA infections resulted in higher presenting C-reactive protein levels (10.4 vs. 7.8 mg/L, P=0.04), longer inpatient stays (10 vs. 5 d, P<0.01), multiple surgical procedures (n>1) (38% vs. 14%, P<0.01), increased sequelae (27% vs. 6%, P<0.01), and more frequent admissions to the intensive care unit (16% vs. 3%, P<0.01). CONCLUSIONS: At our institution over the past decade, we found an approximate 3-fold rise in community-acquired pediatric MRSA musculoskeletal infections accompanied by an elevated risk for complications during inpatient management. Awareness of the epidemiological trends of MRSA within the local community may guide parental counseling and facilitate timely and accurate clinical diagnosis and treatment. LEVEL OF EVIDENCE: Level II-prognostic retrospective study.

External fixation of high-energy tibia fractures.

External fixation (EF) of tibia fractures has been associated with nonunions and malunions at our large pediatric trauma center. This study was designed to determine the successes and shortcomings of EF, especially with respect to maintenance of alignment and time to union. We believe that this will contribute to the limited amount of literature examining the complications associated with this treatment modality in the pediatric population. Thirty-one consecutive high-energy tibia fractures treated with EF over 4.5 years were analyzed. There were 22 boys and 9 girls (4-17 years old; mean, 11.9 years). Mean length of follow-up was 15 months. Of the 31 fractures analyzed, 19 were open fractures (12 closed, 3 grade I, 9 grade II, and 7 grade III). Of 30 fractures, 3 required skin graft, whereas 7 required fasciotomy. Mean duration of EF was 3.2 months. Mean time to union was 4.8 months. For complication rates, 4 of 30 had delayed union, 2 of 30 had nonunion, 8 of 30 had minor malunion, 3 of 30 had major malunion, 3 of 30 had leg length discrepancy, 8 of 30 had pin track infection, 3 of 30 had wound infection, 2 of 30 had osteomyelitis, and 4 of 30 required surgery for nonunion. Time to union differed between those aged 11 years or younger and those aged 12 years or older (means of 3.2 and 6.0 months, respectively; P = 0.001). Union time also differed between those with closed or grade I open fractures and those with grade II or III open fractures (3.9 and 5.7 months, respectively; P = 0.035). Leg length discrepancy rate differed between children aged 11 years or younger and those aged 12 years or older (3/13 and 0/18, respectively; P = 0.05). Although EF has been touted as the standard treatment of high-energy pediatric tibia fractures, our close analysis revealed a high rate of problems such as long union times (especially ages >or=12), malunion, leg length discrepancy (especially ages

Determination of a minimal deletion interval on chromosome band 8p21 in sporadic prostate cancer.

Loss of the short arm of chromosome 8 is a common event in prostatic neoplasms. Previous studies indicate that there may be up to three separate tumor suppressor genes on chromosome arm 8p, based on patterns of allelic loss. The responsible gene or genes have yet to be identified. In the present study, we used laser-capture microdissection of primary human prostate tumors and 17 microsatellite markers across chromosome band 8p21 to determine a minimal deletion interval. From an initial set of 120 cases, three tumors contained overlapping interstitial deletions on chromosome band 8p21. The three cases define an internally consistent minimal candidate tumor suppressor gene interval of approximately two megabases.