Variations of the extensor pollicis brevis tendon and its insertion: a study of 44 cadaveric hands.

The aim of this study was to describe the anatomy of the extensor pollicis brevis tendon, in particular its insertion, in 44 preserved hands from 23 cadavers. We found that only 25% of the tendons were inserted in the conventional way, viz, into the base of the proximal phalanx, and confirmed that the course and insertion of the extensor pollicis brevis tendon varies widely. The importance of these findings to the practice of hand surgery is discussed.

Visualisation of the pisotriquetral joint through standard portals for arthroscopy of the wrist: a clinical and anatomical study.

Disorders of the pisotriquetral joint are well recognised as the cause of pain on the ulnar side of the wrist. The joint is not usually examined during routine arthroscopy because it is assumed to have a separate joint cavity to the radiocarpal joint, although there is often a connection between the two. We explored this connection during arthroscopy and in fresh-frozen cadaver wrists and found that in about half of the cases the pisotriquetral joint could be visualised through standard wrist portals. Four different types of connection were observed between the radiocarpal joint and the pisotriquetral joint. They ranged from a complete membrane separating the two, to no membrane at all, with various other types of connection in between. We recommend that inspection of the pisotriquetral joint should be a part of the protocol for routine arthroscopy of the wrist.

Physical examination of the carpal bones by orthopaedic and accident and emergency surgeons.

Our aim was to test knowledge of carpal bone surface anatomy among orthopaedic and accident and emergency surgeons. A survey of 58 surgeons was conducted. Each was asked to palpate seven points on five commonly injured carpal bones. Eight surgeons declined to participate. Five of the remaining 50 correctly palpated all surface markings. Six failed to accurately palpate even a single point. The scaphoid waist and trapezial ridge were accurately palpated by 47 surgeons. The median score for all participants was 3 correctly identified points. The majority of orthopaedic and accident and emergency surgeons do not perform an accurate physical examination of the carpal bones. The ancient art of history taking, precise physical examination and elucidation of a confident diagnosis is at risk of being replaced with tentative diagnoses and imaging techniques that are expensive and time consuming. We believe that basic anatomical teaching is inadequate.

Scaphoid views: a need for standardisation.

AIMS: Several views are needed to visualise the scaphoid. These are routinely called 'scaphoid views'. The authors believe that asking for scaphoid views from the radiology department often leads to a wide variety and number of radiographic views being taken. METHODS: 50 radiographers were asked which and how many views of the scaphoid they would take, in the acute setting and then in the out-patient department. RESULTS: We found a wide variation in the descriptive terms used by radiographers for particular views. There was also little agreement on how many and which radiographic views to take when asked for 'scaphoid views'. CONCLUSIONS: Not only is there complete lack of agreement on what 'scaphoid views' should be, it was also discovered that there was little agreement on the nomenclature of the individual views themselves. Loss of information can result from the wrong views being taken and unnecessary radiation exposure. We recommend five particular views, which together visualise all areas of the scaphoid.

The osteology of the trapezium.

The present anatomical and clinical literature is not detailed enough for a clear understanding of the three-dimensional anatomy of the trapezium. It lacks descriptions of identifiable landmarks needed for the interpretation of two-dimensional radiographs. Fifty dry cadaver trapezia were assessed and an extended surface anatomy described. New consistent landmarks were described and the tubercle of the trapezium was redefined. The incidence of the salient osteological features in Caucasian trapezia was recorded.

An anatomical database of carpal bone measurements for intercarpal arthrodesis.

During limited intercarpal fusion it is sometimes difficult to determine correct screw length and staple size. This is because of overlap, and the shape and orientation of the carpal bones on radiography. One hundred complete sets of dry cadaver carpal bones were measured to provide an anatomical database of carpal bone measurements. This should help prevent inadvertent overpenetration of fixation devices during surgery.

Intravenous polymethyl methacrylate after cemented hemiarthroplasty of the hip.

Current cementing techniques used during hip arthroplasty aim to maximize the bond at the bone-cement interface in an effort to increase the longevity of the prosthesis. To accomplish this, one must generate high intramedullary pressures, which are known to be associated with complications such as cement implantation syndrome. We record a rare complication following cement pressurization of a hip hemiarthroplasty that resulted in intravenous polymethyl methacrylate (PMMA). This complication however, is not associated with a significant morbidity or mortality, but it is important to identify and distinguish from a femoral cortical defect, which can be created during surgery.

Acute fractures of the scaphoid. Treatment by cast immobilisation with the wrist in flexion or extension?

Acute fractures of the scaphoid were randomly allocated for conservative treatment in a Colles'-type plaster cast with the wrist immobilised in either 20 degrees flexion or 20 degrees extension. The position of the wrist did not influence the rate of union of the fracture (89%) but when reviewed after six months the wrists which had been immobilised in flexion had a greater restriction of extension. We recommend that acute fractures of the scaphoid should be treated in a Colles'-type cast with the wrist in slight extension.

The anatomy of acute scaphoid fractures: a three-dimensional analysis of patterns.

Various classifications of scaphoid fractures have been based on plain radiography, but there are difficulties in defining the actual fracture line without an appreciation of the three-dimensional anatomy. Radiological fracture lines were therefore mapped on transparent methylmethacrylate models of the bone. An analysis of 91 acute fractures showed that 11 were apparently incomplete. The other 80 showed three basic anatomical patterns: transverse through the waist, oblique in the plane of the dorsal sulcus, or of the proximal pole. There was some variation and comminution in these patterns, but no distal fractures of the body were seen. The interpretation of different radiological projections is discussed. The findings have implications for the management and the assessment of outcome.

The radiological anatomy of the scaphoid. Part 2: Radiology.

The complex shape of the scaphoid and its orientation within the carpus makes the radiological interpretation of scaphoid anatomy difficult. To improve our understanding of how the anatomy appears on plain X-ray, a study was performed using dry cadaver bones. Salient anatomical features were outlined using radiopaque markers, the bones set in wax blocks and the blocks X-rayed in the same axis as six "standard" scaphoid views. The pictures obtained were then compared with clinical X-rays.

Fibrolipomatous hamartoma of nerve arising in the brachial plexus.

Fibrolipomatous hamartoma of nerve is a rare benign infiltrating condition of peripheral nerves leading to progressive functional loss. Previous descriptions have virtually all been confined to the distal part of the upper limb, with the median nerve being the commonest reported site. Most cases occur in the first 3 decades of life and a third are associated with macrodactyly. A case is described in a 63-year-old woman, involving the whole of the brachial plexus, a previously unreported site for this particular lesion.

The radiological anatomy of the scaphoid. Part 1: Osteology.

A review of the anatomical and clinical literature found that previous descriptions of the scaphoid were not detailed enough to match our present clinical knowledge or the requirements of modern imaging. With this in mind a revised and extended description has been produced following a study of 50 dry cadaver scaphoids. The incidence of the new features described were assessed in 90 pairs of Caucasian scaphoids.

Imaging the position of a screw within the scaphoid. A clinical, anatomical and radiological study.

In an audit of 68 scaphoid fractures with delayed and non-union that had been internally fixed using the Herbert bone screw, it was found that 39 had a significant fault in screw position. Poor intra-operative imaging was a major contributing factor. An anatomical and radiological study was therefore performed to evaluate which views were necessary in order to be confident about screw position. We recommend a minimum of four views. To display the proximal pole, an ulnar deviated postero-anterior (PA) view and true lateral; and to display the distal pole, a semi-pronated and semi-supinated view.

Dorsal avulsion fractures of the scaphoid: diagnostic implications and applied anatomy.

Three cases of acute dorsal avulsion fracture of the scaphoid are presented. Anatomical and radiological studies indicate that these fractures arise from a ridge on the dorsum of the scaphoid at the distal end of the radial facet. This is not the site suggested by other authors. The clinical significance of these fractures is that they are only visible on the 45 degrees anteroposterior oblique X-ray view of the scaphoid. Without this view they are indistinguishable from X-ray negative scaphoid fractures, since both have similar clinical signs and isotope bone scans.

Trans-carpal injuries associated with distal radial fractures in children: a series of three cases.

Isolated trans-carpal injuries in children are rare. This paper presents three cases of trans-carpal injury associated with an ipsilateral distal radial fracture. Two cases involved simultaneous fractures of the scaphoid and the capitate. The third case involved the scaphoid and the triquetrum. The full extent of these injuries was not recognized on the initial X-rays. If a child presents with a displaced fracture of one carpal bone it may not be an isolated injury.