Soft tissue micro-circulation in the healthy hindfoot: a cross-sectional study with focus on lateral surgical approaches to the calcaneus.

PURPOSE: Open reduction and internal fixation (ORIF) using an extended lateral approach combined with plate osteosynthesis represents the current gold standard in calcaneal fracture treatment, but it is associated with a wound complication rate of up to 30%. Literature suggests that micro-circulation is one of the key factors for sufficient wound healing. The aim of this study was to evaluate soft tissue micro-circulation of the hindfoot in healthy volunteers to determine influencing factors and to identify hypoxic or hypoperfused areas in non-trauma situations, with special attention to surgical approaches. METHODS: Micro-circulation of the lateral hindfoot of 125 participants was non-invasively measured at 2 and 8 mm depths, utilizing a Micro-Lightguide O2C® spectrophotometer. Blood flow (BF [AU]) and oxygen saturation (SO2 [%]) of ten measurement points (MPs) were documented. Demographic factors (age, gender, body mass index [BMI], systolic/diastolic blood pressure, smoking, and pack-years) and regional differences with special regard to surgical approaches (extended lateral approach, Palmer approach, Ollier approach, and a self-modified extended lateral approach) were analyzed. RESULTS: The SO2 assessments at 2- and 8-mm depths revealed higher values in males (p = 0.043; p = 0.025). There was a correlation between higher age and lower 2 mm BF (p = 0.044). Smoking history and number of pack-years did not predict micro-circulation. BF at the 2 mm depth was highest in the regions of Palmer and Ollier approach (p < 0.001). The MP at the distal calcaneal tuberosity showed significantly higher values regarding all parameters (SO2 (2 mm), p < 0.001; SO2 (8 mm), p = 0.001; BF (2 mm), p < 0.001; BF (8 mm), p < 0.001), compared to the surrounding area. CONCLUSIONS: In non-trauma situations, young males were associated with better micro-circulatory supply of the lateral hindfoot. There was a trend for higher blood flow in regions of the Palmer and Ollier approach. The distal calcaneal tuberosity was clearly superior in all micro-circulatory parameters when compared to the surrounding area.

Soft tissue microcirculation around the healthy Achilles tendon: a cross-sectional study focusing on the Achilles tendon and dorsal surgical approaches to the hindfoot.

BACKGROUND: Dorsal approaches to the hindfoot are frequently used. Furthermore, the vascular supply is discussed as a possible cause for ruptures and degeneration of the Achilles tendon. The aim of this study was to evaluate the microperfusion of three possible posterior approaches to the hindfoot and different areas of the Achilles tendon. METHODS: In 111 subjects, a laser Doppler/white light spectroscopy was used to measure microperfusion in terms of blood flow (Flow) and capillary venous oxygen saturation (SO2) in the hindfoot and Achilles tendon. Measurements were performed at two measurement points (MP, proximal and distal) of three dorsal approaches (medial, lateral and central) and inside the Achilles tendon. RESULTS: Microperfusion differed partially between the surgical approaches. The medial and the lateral approaches were significantly superior to the central approach with regard to Flow in both MP (p <  0.001), while SO2 was significantly higher at the proximal measurement point (MP 1; p <  0.001). In this area, the lateral approach was significantly superior to the medial approach regarding Flow (MP 1; p = 0.012). The Achilles tendon exhibited a significantly reduced microperfusion 5 cm proximal to the calcaneal tubercle (SO2 p = 0.001; Flow p = 0.048). Demographic factors, such as body mass index and age, had different effects. Microcirculation was partially superior in men and negatively affected by smoking. CONCLUSIONS: Soft tissue microcirculation on the lateral and medial side of the healthy Achilles tendon was better than centrally on the tendon. Proximally, the lateral approach was better than the medial approach. These circumstances could provide advantages regarding the surgical approach. The Achilles tendon exhibited significantly reduced microperfusion at the typical side of degeneration and rupture. This circumstance could be a possible cause of degenerative processes.

Mortality and cardiorespiratory complications in trochanteric femoral fractures: a ten year retrospective analysis.

PURPOSE: Despite intense research and innovations in peri-operative management, a high mortality rate and frequent systemic complications in trochanteric femoral fractures persist. The aim of the present study was to identify predictive factors for mortality and cardio-respiratory complications after different treatment methods in a ten year period at a level I trauma centre. METHODS: Retrospectively, all patients above 60 years of age with trochanteric femoral fracture between January 2000 and May 2011 were analyzed at a level I trauma centre. Demographic variables, comorbidities, and data regarding the surgical procedures, including required transfusions and post-operative complications, were evaluated, and the in-hospital mortality was recorded. The grade of osteoporosis was classified radiographically using the Singh index. RESULTS: The in-hospital mortality rate was 8.2% among 437 patients (male/female ratio = 110/327, mean age = 81 years) with extramedullary open (n = 144), intramedullary (n = 166), and extramedullary minimally invasive (n = 125) procedures. Significant influential factors on in-hospital mortality were identified with binary logistic regression analysis: an age of ≥90 years (P = 0.011), male sex (P = 0.003), a high American Society of Anesthesiologists (ASA) grade (3-5, P = 0.042), and a high osteoporosis grade (Singh index 3-1, P = 0.011). A total of 21.5% of the study population suffered cardio-respiratory complications post-operatively. The specific mortality was 28.7% (P < 0.001), which was influenced by a high ASA grade (3-5, P = 0.002) and a high transfusion rate (P = 0.004). Minimally invasive locked plating was associated with increased cardio-respiratory complications (P = 0.031). CONCLUSIONS: This study identified high patient age, distinctive comorbidities, male sex, and high osteoporosis grade as significant risk factors for increased in-hospital mortality in the treatment of trochanteric femoral fractures. Furthermore, high ASA grade and a liberal transfusion regime led to an increased incidence of cardio-respiratory complications. Patient-specific characteristics, especially osteoporosis grade and pre-existing medical conditions, may assist in the identification of high-risk patients and allow a patient-specific geriatric co-management plan.

Arthroscopy or ultrasound in undergraduate anatomy education: a randomized cross-over controlled trial.

BACKGROUND: The exponential growth of image-based diagnostic and minimally invasive interventions requires a detailed three-dimensional anatomical knowledge and increases the demand towards the undergraduate anatomical curriculum. This randomized controlled trial investigates whether musculoskeletal ultrasound (MSUS) or arthroscopic methods can increase the anatomical knowledge uptake. METHODS: Second-year medical students were randomly allocated to three groups. In addition to the compulsory dissection course, the ultrasound group (MSUS) was taught by eight, didactically and professionally trained, experienced student-teachers and the arthroscopy group (ASK) was taught by eight experienced physicians. The control group (CON) acquired the anatomical knowledge only via the dissection course. Exposure (MSUS and ASK) took place in two separate lessons (75 minutes each, shoulder and knee joint) and introduced standard scan planes using a 10-MHz ultrasound system as well as arthroscopy tutorials at a simulator combined with video tutorials. The theoretical anatomic learning outcomes were tested using a multiple-choice questionnaire (MCQ), and after cross-over an objective structured clinical examination (OSCE). Differences in student's perceptions were evaluated using Likert scale-based items. RESULTS: The ASK-group (n = 70, age 23.4 (20-36) yrs.) performed moderately better in the anatomical MC exam in comparison to the MSUS-group (n = 84, age 24.2 (20-53) yrs.) and the CON-group (n = 88, 22.8 (20-33) yrs.; p = 0.019). After an additional arthroscopy teaching 1% of students failed the MC exam, in contrast to 10% in the MSUS- or CON-group, respectively. The benefit of the ASK module was limited to the shoulder area (p < 0.001). The final examination (OSCE) showed no significant differences between any of the groups with good overall performances. In the evaluation, the students certified the arthroscopic tutorial a greater advantage concerning anatomical skills with higher spatial imagination in comparison to the ultrasound tutorial (p = 0.002; p < 0.001). CONCLUSIONS: The additional implementation of arthroscopy tutorials to the dissection course during the undergraduate anatomy training is profitable and attractive to students with respect to complex joint anatomy. Simultaneous teaching of basic-skills in musculoskeletal ultrasound should be performed by medical experts, but seems to be inferior to the arthroscopic 2D-3D-transformation, and is regarded by students as more difficult to learn. Although arthroscopy and ultrasound teaching do not have a major effect on learning joint anatomy, they have the potency to raise the interest in surgery.