Biometry of the calcaneocuboid joint: biomechanical implications.

Precise biometric data of calcaneus, cuboid bones and calcaneocuboid joint are not alluded to in textbooks of anatomy. This study focussed on the biometry of 50 calcanei, 30 cuboid dry bones, and anatomical specimens of 21 transverse tarsal joints. Measurement of the length, width, angular orientation, contact surface and radius of curvature, rolling band of the joints surfaces according to the main axes were performed. The results focussed on biometric variations with several morphological types never identified previously. Measurements obtained on dry bones and anatomical specimens with the functions of ligaments were distinguished. The morphology of the calcaneus could explain the results of osteotomy procedures for the treatment of adult flatfoot. A better knowledge of the joint surfaces and biometric data would generate a modeling of the calcaneocuboid joint and function in locking the transverse tarsal joint.

Cortical and trabecular bone distribution in the femoral neck in osteoporosis and osteoarthritis.

The increased hip fragility in osteoporosis has been attributed mainly to a thinning of the cortex. In contrast, hip arthritis (OA) is not associated with increased risk of hip fracture. The purpose of this study was to assess cortical and trabecular bone structures and their possible regional variability in the femoral neck taken from patients who sustained an osteoporotic hip fracture (OP) compared with patients with OA. We compared the distribution of bone in the ultradistal femoral neck in 21 postmenopausal women with OA (mean age: 66+/-7.8 years) and 20 postmenopausal women with an osteoporotic hip fracture (OP) (mean age: 79.5+/-1.9 years). Controlateral hip osteoporosis or osteopenia was confirmed in OP by DEXA (T-score: -2.5+/-0.8 in OP; -0.9+/-1.3 in OA). Histomorphometric parameters of bone structure, architecture and connectivity were measured on sections from the ultradistal part of the femoral neck, divided in 4 quadrants. When compared to OA, cortical thickness was significantly decreased in OP (p<0.0005) but was the highest in the inferior part in both groups. Cortical porosity was higher in OA (13.48+/-1.02 and 8.4+/-1.07% in OA and OP respectively). Compared to OA, the trabecular bone volume was decreased by 50% in OP (p<0.0001) with a diminution of the trabecular number (p<0.01) and thickness (p<0.0001). In parallel, OP group was characterized by a poor connectivity evaluated by the decreased number of nodes (p<0.0001), higher trabecular bone pattern factor (p<0.0001) and greater marrow star volume (p<0.0001). The connectivity was the lowest in the inferior quadrant in OP but not in OA. Our data suggest that in addition to the cortical thinning, the loss of the trabecular bone mass and connectivity plays a role in the skeletal fragility associated with hip fracture. Furthermore, the spatial distribution of the trabeculae differs between OP and OA whereas cortical thinning is homogenous.

[Degenerative cartilage changes in metatarsosesamoidal joint and Scarf procedure results for hallux valgus: a prospective study of 100 cases]. / Les lésions cartilagineuses métatarsosésamoïdiennes dans les résultats de l'ostéotomie Scarf: A propos d'une série prospective de 100 cas.

PURPOSE OF THE STUDY: Sesamoid bones of the hallux play a major role in the biomechanics of the metatarsophalangeal complex. Due to the deformations resulting from hallux valgus, the sesamoid system is exposed to abnormal stress forces. Mapping the degenerative cartilage shows the significant prevalence of these lesions and their relation with the anatomic deformation. The purpose of this work was to determine the impact of these metatarsosesamoidal joint changes on the results of Scarf procedure for hallux valgus. MATERIAL AND METHODS: This series included 89 patients (100 feet) who underwent Scarf osteotomy with complementary phalangeal osteotomy. We distinguished two groups in this cohort: 78 cases of surgery not involving the lateral metatarsals (group A), and 22 cases with associated lateral metatarsal osteotomy (group B). Mean follow-up was 2.3 years; minimal follow-up 16 months. The study protocol was prospective, with preoperative and last follow-up radiological and clinical assessment by an independent operator. Joint lesions noted intraoperatively by one senior operator were noted. The clinical work-up included the AOFAS score. A 15 degrees anteroposterior weight-bearing view was used to determine the degree of sesamoid dislocation and measure the following angles: first metatarsophalangeal angle (M1P1), first intermetatarsal space (M1M2), proximal articular set angle (PASA). Eleven zones were described to map the joint surfaces. The statistical analysis was used to search for links between joint lesions and the radiographic and clinical findings. RESULTS: The joint cartilage analysis revealed lesions involving the sesamoid bones in 72 cases, with a preferential involvement of the medial sesamoid bone (67%). The plantar joint surface of the first metatarsal presented lesions in the medial gutter in 72 cases, and in the lateral gutter in 68. Complete absence of the intersesamoid crest was noted in 38%. The metatarsophalangeal compartment presented degenerative lesions in 15 cases. The preoperative assessment noted a positive significant correlation between the AOFAS overall score and the absence of lesions involving the lateral sesamoid bone (p=0.015), between the AOFAS pain score and the absence of lesions involving the lateral sesamoid bone (p=0.022), between the AOFAS pain score and the complete absence of the intersesamoid crest (p=0.001), between the AOFAS deviation score and the absence of lesion involving the lateral gutter (p=0.001), between the M1P1 angle and the absence of an intersesamoid crest (p=0.001). At last follow-up, there was a positive significant correlation between the absence of lesions involving the medial sesamoid bone and a better overall AOFAS score (p=0.014), between absence of a lateral sesamoid lesion and better postoperative sentering of the sesamoids (p=0.014), between the absence of lesion in the medial gutter and a higher postoperative M1P1 angle (p=0.002), between the absence of lesions involving the lateral gutter and more favorable overall AOFAS score (p=0.005) for function (p=0.022), and deviation (p=0.018), between the absence of intersesamoid crest lesions and better radiographic sesamoid recentering (p=0.020). Distinct analysis of groups A and B did not demonstrate a significant difference compared with the overall cohort. Comparison of the two groups only demonstrated three significant differences involving radioclinical parameters. DISCUSSION: Hallux valgus is associated with very frequent metatarsosesamoid lesions. The distribution of these lesions is a function of the anatomic and biomechanical features of the metatarsosesamoid joint surfaces. Lesions to the lateral compartment would be a poor prognostic factor for Scarf procedure.

[Selective dorsal T1-T6 fusion of the thoracic spine and effects on thorax growth: experimental study in prepuberal New Zealand White rabbits]. / Influence de l'arthrodèse vertébrale dorsale sélective T1-T6 sur la croissance thoracique: étude expérimentale chez des lapins New Zealand White prépubertaires.

PURPOSE OF THE STUDY: The purpose of this study is to assess the consequences brought by selective dorsal arthrodesis of thoracic spine (T1-T6) to the growth of spine and thoracic volume in operated and sham-operated New Zealand White rabbits, between prepubertal age and the end of somatic growth, through the study of computerised tomography (CT) scans periodically carried out on them after arthrodesis surgery. MATERIAL AND METHODS: Nine female rabbits were subjected to surgery for selective dorsal arthrodesis of the upper thoracic spine and three were sham-operated. Surgery was performed at age nine weeks, before the onset of puberty. Two "C"-shaped titanium bars were placed beside the spinous processes of the thoracic vertebrae to obtain a selective posterior arthrodesis of the first six thoracic vertebrae. Under general anesthesia, three CT scans were performed, 10 (t1), 55 (t2) and 139 (t3) days after surgery. Measures were obtained by Myrian Pro software for three different groups: group 1 with complete fusion, group 2 with incomplete fusion, group 3 sham-operated. RESULTS: The total dorsal and ventral lengths of thoracic vertebral bodies in the spinal segment T1-T6 was smaller in group 1 and group 2 than in group 3, whereas no differences were observed between the three groups in the T7-T12 segment. The average of the dorsoventral/laterolateral thoracic diameter ratio at fused levels was less than 1 in group 1 as well as in group 2; on the contrary, in group 3 it was greater than 1. The sternum and lung volume grow less. CONCLUSIONS: Vertebral arthrodesis in the treatment of progressive idiopathic scoliosis in prepubertal patients is not ideal, but is still a choice in treating major deformities of the spine. Postoperative assessment of spinal deformity is essential, feasible and recordable through CT scans. Dorsal arthrodesis in prepubertal rabbits changes thoracic growth patterns. In operated rabbits, the dorsoventral thoracic diameter grows more slowly than the laterolateral thoracic diameter. The sternum, the total lengths of thoracic vertebral bodies in the spinal segment T1-T6 and lungs grow less. The Crankshaft phenomenon is evident at the fused vertebral levels where there is a reduction of thoracic kyphosis.

[Degenerative changes of the metatarso-sesamoido-phalangeal complex]. / Lésions dégénératives du complexe métatarso-sésamoïdo-phalangien.

OBJECTS: The aim of this work was to determine the frequency and the location of the degenerative lesions of the hallucal metatarsophalangeal joint in an elderly population. Our results help us to precise the anatomic characteristics of that articular complex. METHODS: Our material comprised 21 feet from embalmed cadaver specimens. We studied the morphometrical parameters for the anatomic description of the first metatarsophalangeal joint of the forefoot. After complete dissection, a specific articular zone-mapping was made with a quantitative evaluation of the chondral lesions. MAIN RESULTS: The measurements of the morphometrical parameters were in accordance with the literature data. The sesamoidal chondral lesions were more frequent for the medial sesamoid and at the proximal zone of the articular surface. The plantar metatarsal lesions were very frequent with diffuse or distal groove damage, and crista damage linked to the sesamoidal strap dislocation. The lesions involving the metatarsophalangeal compartment were less frequent and rather at the dorsal zone. CONCLUSIONS: The degenerative lesions of the metatarso-sesamoido-phalangeal complex are nearly systematic in n elderly population. The morphological aspect of these lesions is very characteristic of the articular function and allows us to precise the biomechanic constraints.

[Carpal model and biomechanics]. / Modélisation du carpe osseux et biomécanique.

Carpal morphology and orientation of carpal bones are usually studied on two-plane radiography. Those measurements depend on the incidence of X-ray and on the expertise of physician. A method that eliminates both should improve the accuracy of those measurements. The digital data from computed tomography scans can be use to describe carpal geometry. We defined biometric and angular parameters allowing the study of carpal morphology and bones orientation. From digital data from computed tomography scans software can obtain bone volume, inertia principal axis and volume of ellipsoid of inertia. Bone centroid location and principal axis orientation can be used to study bones orientation. 3D distances ratio between geometry centroid of carpal bones. The measurements allowed by this methodology are numerous. A study of a more consistent series of normal wrists will allow in the future for each quantitative parameter to define the normal range. A comparative study of normal wrists and pathology wrists should allow defining, for each pathology, the most judicious quantitative parameters.

[The human body and the computer as pedagogic tools for anatomy: review of the literature]. / Le corps humain et l'informatique comme outils pédagogiques de l'anatomie.

Since the first dissections, the human body has been the main tool for the teaching of anatomy in medical courses. For the last 30 years, university anatomy laboratory dissection has been brought into question and the total hours of anatomy teaching have decreased. In parallel, new technologies have progressed and become more competitive and more attractive than dissection. The aim of this review of the literature was to evaluate the use of the human body as a pedagogic tool compared to today's computer tools. Twenty comparative studies were reviewed. Their analysis showed that the human body remains the main tool in anatomy teaching even if anatomic demonstration (prosection) can replace dissection, and that the computer tools were complementary but not a substitute to dissection.

Tophaceous gout of the patella with primary hyperparathyroidism.

The case of an 81-year-old woman with persistent post-traumatic pain of the knee linked to tophaceous gout of the patella is presented. This gout was associated with adenomatous primary hyperparathyroidism. The relationship between hyperuricemia, hyperparathyroidism and chronic renal failure is discussed.

Sacral insufficiency fractures presenting as acute low-back pain. Biomechanical aspects.

Sacral insufficiency fractures are an often unsuspected cause of low-back pain in elderly women with osteopenia who have sustained unknown or only minimal trauma. The authors describe 10 cases of spontaneous sacral insufficiency fractures, confirmed by computed tomography, characterized by the onset of acute low-back pain. Differential clinical and radiographic diagnosis of these fractures is often difficult. Recognition of the characteristic scintigraphic patterns in sacral fractures, which are frequent in osteopenic patients, could avoid mistaken diagnoses and unnecessary tests or treatment. One of the striking feature of these sacral fractures is their invariable location. The fractures extend vertically in the sacral alae, parallel to the sacroiliac joints. They are located just lateral to the margins of the lumbar spine. This distribution suggests that such fractures could be partially caused by weight-bearing transmitted through the spine.

Multiple psoas abscesses after posterior spinal fusion.

STUDY DESIGN: A case of multiple psoas abscesses after Dove lumbar spine fixation is reported. OBJECTIVES: To review the diagnosis and treatment of deep infection after internal spinal fixation. METHODS: The possibility of septic complications after spinal surgery that may present with a degenerative pattern is examined. The clinical and computed tomographic findings of a psoas abscess are recalled. RESULTS: Surgical drainage of the purulent collection was performed along with prolonged parenteral antibiotic treatment. CONCLUSION: Infection should be considered as a cause of recurrence of pain after internal fixation of the lumbar spine.

New concepts on the arterial vascularization of skin and muscle.

From a personal anatomic study, the author describes here the principles of cutaneous and muscular arterial blood supply and proposes a new classification. The cutaneous arterial blood supply depends on musculocutaneous arteries and on direct cutaneous arteries. With the exception of some cutaneous flaps that are supplied by direct cutaneous arteries, most other cutaneous areas are supplied by musculocutaneous arteries. The dissection of a fasciocutaneous flap reveals a new possibility for repairing large skin defects. The subcutaneous aponeurosis possesses a rich vascular supply and an important arterial network. The muscular arterial blood supply is fully studied here with the description of two main groups of muscles corresponding to an adequate blood supply.

The effect of different porosities in coral implants: an experimental study.

Goniopora lobata and polyphyllia talpina were tested in 10 sheep with a follow-up of 12 months. The reference material was a glass ceramic CAP 42. Different implantation sites are used: craniofacial and orthopaedic. A macro and microscopic postoperative study was performed at 3, 6, 9 and 12 months. The results show: (1) biocompatibility with bone and soft tissues; (2) disappearance, without colonisation, of Goniopora Lobata associated with complete bone regeneration at 12 months and (3) later resorption of polyphyllia talpina with a fibrous colonisation, without osseous transformation. The possibility of using these materials in cranio-maxillo facial surgery is discussed.

Anatomical study of the ulnar nerve in the hand.

This anatomical study is based on the dissection of fifty adult hands. The classic configuration of the ulnar nerve was found in thirty-nine cases out of fifty, and in eleven cases there were variations with respect to division. The levels of division of the different branches were precisely determined by an analysis of variations in the areas of muscular innervation.

Avulsion of the flexor digitorum profundus tendon associated with a chondroma of the distal phalanx.

An avulsion of the profundus tendon associated with a chondroma of the distal phalanx is presented. The injury occurred during housework and the tendon avulsion can be explained by a weakness of the profundus tendon insertion.

Tophaceous gout of the navicular bone as a cause of medial inflammatory tumor of the foot.

A case of tophaceous gout of the navicular bone in a 24-year-old woman is reported. Emphasis is placed on the conditions that might have been precipitating, i.e., anorexia nervosa and alcoholism, and the mechanisms by which increased uric acid level may be explained. The main radiographic patterns of tophaceous gout of the foot are recalled to avoid unnecessary surgery in future cases.

[CRST syndrome. Ultrastructural and physico-chemical studies of calcifications (author's transl)]. / Syndrome CRST. Etude ultrastructurale et physico-chimique des calcifications.

The subcutaneous calcifications in a case of CRST syndrome were studied by electron microscopy and by several physico-chemical tests in order to establish their structure and development. Samples of powder, obtained by crushing and homogenisation of the deposits, were subjected to the following analyses: - radiocrystallography by X-ray of the raw and heated material - infra-red spectroscopy before and after heating - quantitative chemical analysis and differential thermal micro-analysis. Connective tissue fibres seemed to play an important part in the development of the calcifications. The initial deposits of calcium first appeared in the central part of elastic fibres whose general morphology remained nevertheless undisturbed. In the older deposits disorganised elastic (and possibly collagen) fibres and areas of bone formation were found. Evidence of an inflammatory reaction was always minimal or nil. There was considerable variation in the calibre of collagen fibres in the non-calcified zones, the smaller fibres predominating. These appearances, sometimes noted in scleroderma, seem to be associated with increased collagen synthesis. X-ray diffraction and infra-red spectroscopy studies show that the deposits consist essentially of type B hydroxyapatite carbonate, confirmed by differential thermic analysis. On electron microscopy the calcifications were shown to comprise straight, needle-like crystals, 100-600 nm in length and 30-100 nm broad, characteristic of the apatites. Very occasionally, target-pattern deposits conforming to whitlockite were encountered. Chemical analysis revealed a high proportion of calcium with a Ca/P ratio greater than 1-666 as is typical of synthetic hydroxyapatite carbonates. The deposits also contained up to 20% by weight of organic material.

[Spiral (helical) CT of tracheobronchial diseases]. / La tomodensitométrie spiralée (hélicoïdale) en pathologie trachéobronchique.

The acquisition techniques, including some important dosimetric considerations, and the reconstruction methods reviewing the tomographic, bronchographic and endoscopic rendering techniques are first taken into consideration. They are applied to the most usual problems and diseases encountered in the daily activityThe main purpose of this review, which merges the modern technology of spiral (helical) CT with the multislice acquisition in the very near future, consists in delivering, whenever possible, an integrated diagnostic and therapeutic approach of imaging, endoscopy and surgery.

[Assessment of carpal bone maturation by imaging: an alternative to bone age determination or a complementary study?]. / L'évaluation de la maturation des os du carpe par analyse d'image: une alternative à l'âge osseux ou un outil complémentaire?

Radiographic evaluation of skeletal maturation with or without automated systems relies on the comparison between the radiographic appearance of portions of a child's skeleton and the standardized appearance in a comparable population of children. Assessment of skeletal maturation using image analysis of wrist computerized-assisted tomography is a quantitative method allowing for measurements of the volume of each carpal bone, the axis of inertia, and the mean bone density. Morphological modifications of carpal bones are characterized by quantitative data relating to the length of the axis of inertia and the volume. Imaging is a potentially useful method for carpal bone assessment during growth.

[Interpretation of thoracic radiographs re-examined and corrected with tomodensitometry]. / L'interprétation d'une radiographie thoracique revue et corrigée par la tomodensitométrie.

To our knowledge, conventional chest radiography is not likely to become obsolete or disappear from the daily practice of medical imaging. As such, it is important to insure that chest radiographs are acquired using optimal technique. Evaluation of chest radiograph findings must be comprehensive and the art of reading chest radiographs must be well thought to physicians in training. Chest radiography is characterized by the projection of tridimensional anatomical structures and disease processes onto a two-plane radiographic film. Correlation with cross-sectional data obtained from CT may greatly enhance the understanding and interpretation of conventional chest radiographs. Indeed, review of CT images facilitates anatomical understanding of the segmental and subsegmental anatomy, of the superior segments of the lower lobes and of the three dimensional orientation of the fissures. CT also has improved the understanding of some chest radiography findings. Careful review of findings at chest radiography is helpful to optimize CT acquisition protocols in order to reduce some of the pitfalls of CT and improve detection of specific processes that could otherwise be poorly demonstrated or overlooked. Chest radiographs can sometimes detect diseases or abnormalities that are difficult to demonstrate at CT.