Obesity has been associated with higher complication rates and poorer outcomes following joint replacement surgery. Body mass index (BMI) is a simple index of body composition and forms part of preoperative assessment. It does not take into account the proportion of lean mass and body fat and can give a false impression of body composition in healthy manual workers. A more accurate measure of body composition is available using non-invasive bioimpedance methods. This study aims to identify whether BMI provides an accurate measure of body fat composition in patients awaiting lower limb arthroplasty surgery. Consecutive patients attending for pre-assessment clinic prior to total knee and hip replacement surgery were examined. All patients had their BMI calculated and underwent bioimpedance testing using a bedside Bodystat 1500 scanner (Bodystat, UK).Introduction
Methods
To determine the current practice of scoliosis surgery in the UK. A 10 point questionnaire was constructed to identify the philosophy of surgeons on various aspects of scoliosis surgery such as choice of implant, bone graft, autologous blood transfusion (ABT), cord monitoring and computer assisted surgery. Results are compared with the current best evidence. Consultants and Fellows attending the 2009 British Scoliosis Society meeting. 50 questionnaires were completed: 45 Consultants and 5 Fellows. All pedicle screw construct favored by 25/50, hybrid 24/50 (one undecided). Posterior construct of less than 10 levels, 20/50 would not cross-link, 11/50 used one and 19/20 used two or more. More than ten levels 17/50 considered cross-links unnecessary, 4/50 used one and 29/50 used two or more. 88% preferred titanium alloy implants, while a mixture of stainless steel and cobalt chrome was used by others. For bone graft, substitutes (24), iliac crest (14), allograft (12) and demineralised bone matrix (9) in addition to local bone. 10/50 would use recombinant bone morphogenetic protein (3 for revision cases only). 39/50 routinely used intra-operative cell salvage or ABT drains and 4/50 never used autologous blood. All used cord monitoring, Sensory (19/50), Motor (2/50) and combined (29/50). None used computer-aided surgery. 26 operated alone 12 operated in pairs and 12 varied depending on type of case. This survey has brought to light interesting variations in scoliosis surgery in UK. It may reflect the conflicting evidence in the literature.
Wire crossing angle affects the stability of circular fine wire frames. Anatomical atlases document safe ‘corridors’ to avoid neurovascular structures, although this may limit crossing angle. In the distal tibia the furthest posteriolateral safe corridor described is through the fibula. The present study describes a new and safe ‘retro-fibular’ corridor for wire placement in the distal tibia that provides a greater crossing angle. Two different methods of wire insertion are considered to determine which provides greater protection to neurovascular structures. A dissection based study of 20 embalmed lower limbs divided into two groups. 1.8mm wires were inserted at increments along the tibia, from posterolateral to antero-medial, at 30–45 degrees to the sagittal plane. In the first group wires were placed against the posterior surface of the fibula and ‘stepped’ medially onto the tibia. In the second wires were inserted midway between the border of the fibula and tendoachilles. Standard dissection techniques were used to identify the path of wires and distance from neurovascular structures. In group one distal tibial wires avoided the posterior tibial neurovascular bundle (mean distance 21.7mm) although passed close to the peroneal artery (mean distance 1.2mm). In group two both the posterior tibial and peroneal structures were avoided (mean distances 15.5mm and 7.1mm respectively). Comparison of the two groups shows a significant difference (p<
0.001). Retrofibular wire placement is safe in the distal quarter of the tibia and facilitates an optimal crossing angle, although is not described in standard atlases. Insertion of wires mid-way between the posteromedial border of the fibula and the tendoachilles appears the most reliable technique.
