The modified anterolateral approach to the humerus.

INTRODUCTION: The anterior and anterolateral approaches to the humerus describe splitting brachialis longitudinally, assuming its fibres run parallel to the shaft. Recent improvements in the understanding of brachialis anatomy however have demonstrated it has two distinct heads, with the bulk of its fibres running oblique relative to the humerus. Attempting to split brachialis longitudinally to the extent required for plate osteosynthesis invariably leads to transection of a significant number of muscle fibres. The authors present a less muscle destructive modification to the anterolateral approach (ALA) based on a bicipital brachialis muscle. METHOD: In order to preserve brachialis muscle fibres, the modified ALA elevates the superficial head from the underlying humerus and longitudinally splits the deep head to allow a fixation device to be tunnelled. Case notes of patients with a humeral shaft fracture fixed via the modified ALA were retrospectively reviewed. RESULTS: Ninteen humeral shaft fractures were fixed via the modified ALA. No post-operative nerve palsies were reported. Of the 19 patients, 14 (73.7%) received clinical and radiological follow-up. All reported being satisfied with their outcome. One developed a superficial wound infection and one (previous diagnosis of spondyloepiphyseal dysplasia tarda) developed a non-union requiring revision surgery. Of the five patients lost to follow-up, two died, and three reported no ongoing orthopaedic issues via telephone. CONCLUSIONS: Improved anatomical understanding of brachialis has resulted in the described modification to the ALA which is less muscle destructive and follows a truer inter-nervous plane. This small series demonstrates satisfactory outcomes using this approach.

The distal radius palmar cortical angle in adolescent versus adult populations.

PURPOSE: Volar distal radius plates are pre-contoured to aid restoration of anatomy during open reduction internal fixation of distal radius fractures. Incorrectly contoured plates can result in malreduction, leading to malunion, pain, and loss of function. The purpose of this study was to investigate whether adolescent distal radius anatomy on the palmar cortical surface differs from that in adults, in order to determine whether adult plates are suitable for use in adolescents. METHODS: Lateral wrist radiographs were used to measure the distal radius palmar cortical angle (PCA) in adolescent age groups (12-13, 14-15, and 16-17 years old) and compared to a skeletally mature control group (30-50 years old). Two assessors measured 423 PCAs twice. RESULTS: There was a statistically significant ( p = <0.05) difference in the PCA of the control group compared to each adolescent group. The mean PCA for both males and females decreased as age increased (increasing curvature of the volar distal radius with age). The mean PCA (male/female) was 164.38°/163.00° in ages 12-13, 162.14°/160.92° in ages 14-15, 157.52°/158.18° in ages 16-17, and 149.65°/154.03° in the control group aged 30-50 years. Agreement between assessors was high with an Interclass correlation coefficient (ICC) of 0.97. CONCLUSION: There is a statistically significant and potentially clinically important difference in the curvature of the distal radius volar cortex between adolescents and adults. This difference persists even in the 16-17 age group. As the PCA curvature is significantly greater in adults compared to adolescents, plates pre-contoured for adults may lead to malreduction of distal radius fractures into flexion in adolescent patients.

The use of ultrasound in comparison to radiography in magnetically controlled growth rod lengthening measurement: a prospective study.

PURPOSE: This study investigated whether ultrasound (U/S) is an alternative to radiography when measuring magnetically controlled growth rod (MCGR) length in order to reduce radiation exposure. Distractible spinal growth rods are the gold standard when treating early-onset scoliosis (EOS). METHODS: This was a prospective series. Patients were already undergoing EOS treatment using MCGRs. Forty-eight data points measured using radiography and U/S were compared. Each U/S data point was measured three times by three observers to assess intra- and inter-observer reliability. The radiation dose of the pre-lengthening and post-lengthening radiographs was recorded. RESULTS: The average rod lengths were 1.322 cm with U/S and 1.329 cm with radiography. The ICC (radiography vs. U/S) was 0.992 (95 % confidence interval (CI) 0.976, 1.000). The inter- and intra-rater reliability of U/S had an ICC of 0.987 (95 % CI 0.966, 1.000) and 0.983 (95 % CI 0.956, 1.000), respectively. The mean total effective radiation dose of the pre-lengthening and post-lengthening PA spinal radiographs was 0.26 mSv with a mean attributable lifetime cancer risk of one in 39,686 per lengthening. CONCLUSION: U/S highly agrees with radiography when measuring MCGR length. It has a high inter- and intra-observer reliability and does not require radiation exposure. Although U/S allows accurate MCGR measurement and soft tissue assessment, patients will still need occasional radiographs to assess spine bony elements, overall spinal balance and scoliosis correction. Combining radiography and U/S allows patient monitoring and accurate MCGR measurement whilst decreasing patients' radiation exposure.

Pyogenic liver abscess trends in South Australia.

BACKGROUND: Pyogenic liver abscess (PLA) is an uncommon but potentially life-threatening condition. Due to advances in diagnostic and treatment methods, the mortality rate has reduced in recent decades. The aim of this study was to gather recent data to examine PLA trends in South Australia. METHODS: The medical records of all patients admitted to The Queen Elizabeth Hospital, South Australia, between November 2000 and November 2009 with a primary or secondary diagnosis of PLA were retrospectively reviewed. RESULTS: Thirty-six patients were identified. Twenty (55.6%) were male and 16 (44.4%) female. The mean patient age was 70.2 years. A single PLA was found in 21 (58.3%) patients and multiple abscesses in 15 (41.7%) patients. Segment 7 of the liver was most commonly affected (10 cases). In 12 patients, multiple organisms were identified. Escherichia coli, Klebsiella pneumonia and Streptococcus species were most commonly identified. All patients received antibiotics and 27 (75%) received additional treatment. Nine patients received open abscess drainage. Fourteen received ultrasound-guided or computed tomography-guided percutaneous drainage or aspiration. One patient died as a direct result of a PLA. DISCUSSION: Since its first description, the epidemiology of PLA has changed. Patients diagnosed with PLA are now older, the male predominance is less and the organism more likely to originate from the biliary tract. The approach to PLA has also progressed with more accurate imaging and better treatment methods becoming available, which has resulted in a low mortality rate. This series confirms the described trends in South Australia.

A comparison of wound area measurement techniques: visitrak versus photography.

OBJECTIVE: To investigate whether a cheap, fast, easy, and widely available photographic method is an accurate alternative to Visitrak when measuring wound area in cases where a non-wound-contact method is desirable. METHODS: The areas of 40 surgically created wounds on porcine models were measured using 2 techniques-Visitrak and photography combined with ImageJ. The wounds were photographed with a ruler included in the photographic frame to allow ImageJ calibration. The images were uploaded to a computer and opened with ImageJ. The wound outline was defined from the photographic image using a digital pad, and the ImageJ software calculated the wound area. The Visitrak method involved a 2-layered transparent Visitrak film placed on the wound and the outline traced onto the film. The top layer containing the tracing was retraced onto the Visitrak digital pad using the Visitrak pen and the software calculated the wound area. RESULTS: The average wound area using the photographic method was 52.264 cm(2) and using Visitrak was 51.703 cm(2). The mean difference in wound area was 0.560 cm(2). Using a 2-tailed paired T test, the T statistic was 1.285 and the value .206, indicating no statistical difference between the two methods. The interclass correlation coefficient was 0.971. CONCLUSIONS: The photographic method is an accurate alternative to Visitrak for measuring wound area, with no statistical difference in wound area measurement demonstrated during this study. The photographic method is a more appropriate technique for clean and uncontaminated wounds, as contact with the wound bed is avoided.