Statistical shape models of cuboid, navicular and talus bones.

BACKGROUND: The aim was to develop statistical shape models of the main human tarsal bones that would result in novel representations of cuboid, navicular and talus. METHODS: Fifteen right and 15 left retrospectively collected computed tomography data sets from male individuals, aged from 17 to 63 years, with no known foot pathology were collected. Data were gathered from 30 different subjects. A process of model building includes image segmentation, unifying feature position, mathematical shape description and obtaining statistical shape geometry. RESULTS: Orthogonal decomposition of bone shapes utilising spherical harmonics was employed providing means for unique parametric representation of each bone. Cross-validated classification results based on parametric spherical harmonics representation showed high sensitivity and high specificity greater than 0.98 for all considered bones. CONCLUSIONS: The statistical shape models of cuboid, navicular and talus created in this work correspond to anatomically accurate atlases that have not been previously considered. The study indicates high clinical potential of statistical shape modelling in the characterisation of tarsal bones. Those novel models can be applied in medical image analysis, orthopaedics and biomechanics in order to provide support for preoperative planning, better diagnosis or implant design.

Statistical, Morphometric, Anatomical Shape Model (Atlas) of Calcaneus.

The aim was to develop a morphometric and anatomically accurate atlas (statistical shape model) of calcaneus. The model is based on 18 left foot and 18 right foot computed tomography studies of 28 male individuals aged from 17 to 62 years, with no known foot pathology. A procedure for automatic atlas included extraction and identification of common features, averaging feature position, obtaining mean geometry, mathematical shape description and variability analysis. Expert manual assistance was included for the model to fulfil the accuracy sought by medical professionals. The proposed for the first time statistical shape model of the calcaneus could be of value in many orthopaedic applications including providing support in diagnosing pathological lesions, pre-operative planning, classification and treatment of calcaneus fractures as well as for the development of future implant procedures.

Custom made total hip replacement--necessary or not?

Indication and technical requirements analyses for custom made THR have been made. Indications for the use of custom made THR and the results achieved have been assessed according to the available literature and compared to the results of standard THR. There is a significant divergence in indications, late results and production costs. Clinical reports focus mostly on individual project metric data preparation method, technical aspects (such as shape or used material) or implantation method. Biomechanical analysis of achievable range of motion, ways of load transportation and equalization of frequently substantial discrepancy in leg length, is more hypothetical. The difficulty stems from the soft tissue quality which cannot be determined precisely, the cause of contracture or dynamic dysfunction triggered by the change of muscle action axis and muscle force over the joint, after changes of offset and joint axis of motion. In complicated cases, preoperative planning of a single approach/solution strategy can pose severe difficulties which would be hard to overcome during operation. Analysis was based on 2 cases.

Evaluation of follow-up results of McBride operative treatment for hallux valgus deformity.

BACKGROUND: Hallux valgus still remains a problem in orthopaedic surgery, a fact attested to by over a hundred operating procedures for the correction of this deformity that have been elaborated until now. The aim of the study was to evaluate the results of the McBride procedure for surgical correction of the hallux valgus deformity using an anatomic & functional foot scoring system and roentgenometric assessment. MATERIAL AND METHODS: 121 feet in 65 women who underwent the McBride procedure for a hallux valgus deformity at the Orthopaedic Department of the Wroclaw University of Medicine in the years 1995-2001 were analysed. The follow-up period varied from 4 to 11 years, for an average of 6.5+4.2 years. Foot function was assessed with a scoring system developed by the author. The roentgenometric examination comprised the following parameters: hallux valgus angle, intermetatarsal angle 1-2, metatarsal I varus angle, and medial sesamoid displacement. RESULTS: After the operation the number of painless feet as well as walking ability increased. The number of bunions and the number of painful callosities beneath metatarsal heads also decreased in a statistically significant manner. The average hallux valgus angle on physical examination decreased by 17.2 o. The mean overall functional score increased from 31.2 to 74.1 points, i.e. it rose by two categories, from 'poor' to 'good'. The overall satisfaction rate (excellent and good results) was 76.9%. There were 4 cases (3.3%) of hypercorrection and 14% of the 121 patients experienced a recurrence of the valgus deformity. CONCLUSIONS: The McBride procedure is still useful in the treatment of hallux valgus for selected groups of patients, on condition that the qualification criteria are very strictly adhered to.

Evaluation of nonunions of the tibia diaphysis - own experience.

BACKGROUND: Delayed union is not an expected outcome of treatment of a bone fracture. The cause of the delayed union must be established before treatment of the complication can be undertaken. The method of treatment depends mainly on the specific nature of delayed bone union. The study evaluates the causes of delayed bone union during treatment of tibial shaft fractures. MATERIAL AND METHODS: Seventy-two patients with delayed union following a fracture of the tibial diaphysis were treated in the Department of Orthopaedics and Musculoskeletal Traumatology of Wroclaw Medical University between 1995 and 2005. All patients had received previous treatment of the fractures. Depending on the morphology of the delayed union, the treatment was with Ilizarov's compression-distraction method or autologous osteoplasty with intramedullary, internal or external fixation. The choice of a method was based on an analysis of the features of the non-union while fracture morphology, presence of other concomitant sequelae of the original injury, fixation method and possible surgical errors, post-operative patient management, co-morbidity and patient compliance were evaluated as risk factors of delayed bone union. The risk factors were subdivided into treatment-dependent (external) and treatment-independent (internal). Treatment outcomes were evaluated on the basis of an orthopaedic examination and radiographic evidence. RESULTS: In the vast majority of patients, delayed union of the tibial diaphysis was due to external factors. CONCLUSIONS: Delayed union of the tibia can be avoided through early and simultaneous treatment of all sequelae of the original trauma. Patient management must be based on state-of-the-art medical knowledge.

The value of autotransfusion in the management of intraoperative blood loss during orthopedic surgery.

The principal advantage of autologous blood transfusions is the danger of transmitting infectious agents and the adverse immunomodulatory effects of allogenic transfusion can be avoided. The effectiveness of preoperative autologous blood donation in reducing allogenic blood exposure is undisputed. The current discussion focuses on cost effectiveness versus the potential risks of autologous blood donation, and on transfusion criteria for autologous versus allogenic blood. The cost effectiveness of autologous blood donation may indeed be low, mainly due to the high percentage of units discarded. On the basis of current literature, the authors describe various types of autotransfusion, current opinions the regarding benefits and risks of autotransfusion, and some of the economic aspects of autotransfusion.

Assessment of Ilizarov's method in intraarticular calcaneal fractures.

Background. Hindfoot dysfunction after intrarticular fracture of calcaneus are evokated by disturbances of muscle balance caused by change of bone shape and disturbances of talo-calcanear join function caused by secondary arthrosis of the joint. Goal of fracture treatment is restoring joint surfaces and the shape of calcaneus. It allow restoring function of foot and a correct gait. Material and methods. In the years 1997-2002 in Department of Orthopedic and Traumatology of Wroclaw Medical University 45 patients with intrarticular fractures of calcaneus were treated. Closed reduction as well as external stabilisation with the use of Illizarov fixator was applied in 20 patients as method of choice, in accordance to our criteria. Observation period of the treated group extended from 6 months to 6 years. Results. To investigation answered 25 patients (21 men and 4 woman). In this group 11 patients with 14 fractures of calcaneal bone were treated with Ilizarov method. Restoration of anatomical conditions and secondary arthrosis were evaluated on the basis of x-ray examination and functional result of treatment simultaneously according to Olerud, Molander and Rowe evaluation form. Conclusions. In our analysis application of closed reduction and external fixation with Ilizarov device is a method of choice in cases when selected criteria are fulfilled.