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Objective: To examine the fracture failure surfaces from Thoroughbred horses that had sustained a catastrophic condylar fracture., Sample Population: Bone specimens from the failure surface were obtained from 12 Thoroughbred racehorses with catastrophic injury and 2 non-racing horses with accidental long bone fracture., Methods: Bone specimens from the failure surface of each fracture were incubated with gold microspheres to label microcracks before examination at x50 to x60,000 using scanning electron microscopy. Microcracking at the failure surface was assessed using a visual analog scale., Results: Branching arrays or clusters of microcracks were seen over a range of magnifications in adapted subchondral bone in the distal end of the MC3/MT3 bone from racing Thoroughbreds with a catastrophic displaced condylar fracture. In the palmar/plantar region, microcracking was associated with the formation of an array of macroscopic cracks in the condylar groove. A different pattern of microcracking was seen in specimens of bone from distal metaphyseal and diaphyseal MC3/MT3 failure surfaces from Thoroughbred racehorses with catastrophic fracture and non-racing horses with an accidental diaphyseal long bone fracture. Few microcracks were seen and typically did not form branching arrays., Conclusion: These data suggest that propagation of condylar fracture in Thoroughbred racehorses is initiated by the formation of nanoscale microcracks in adapted subchondral bone that form during exercise-induced bone adaptation., Clinical Relevance: Accumulation and coalescence of branching microcracks into arrays or clusters appears to eventually lead to the development of macroscopic subchondral cracks in the condylar groove and initiation of a condylar fracture.

Avascular necrosis of the third metacarpal head is a rare entity. It may remain asymptomatic, but may also be painful and lead to restricted range of motion. A-thirteen-year-old male patient presented with a painful and restricted range of motion in the third metacarpophalangeal (MCP) joint. There was no history of any trauma or a predisposing factor such as systemic lupus erythematosus or steroid use. The range of motion of the involved joint was minimally restricted (flexion range, 10 to 80 degrees). Mild tenderness was found on palpation over the dorsal aspect of the third MCP joint. Radiographs showed flattening and sclerosis of the third metacarpal head together with cystic lesions. The symptoms were controlled with non-steroidal anti-inflammatory drugs and splinting for four weeks. The range of motion of the MCP joint increased, along with regression on radiographs.

Millions of Americans suffer from osteoarthritis, a joint disease characterized by cartilage degradation and subchondral bone sclerosis. However, little is known about its pathology. It remains to be discovered which comes first in the progression of osteoarthritis: subchondral bone remodeling or cartilage degeneration. This study assessed equine cartilage degeneration, based upon measurements of cartilage thickness and Indian ink stain uptake. By gaining a greater understanding of the determining factors in cartilage degeneration, we may be able to better understand the pathomechanics of osteoarthritis. In seven horses, joint regions of interest were harvested bilaterally and isolated into planar osteochondral samples using a band saw and stored at -20 degrees C. After thawing, the samples' articular surfaces were dyed using an Indian ink stain to highlight articular cartilage degeneration. Digital images of the samples were taken before and after the staining, and mean pixel values for the pre- and post-ink images were measured using image analysis software. Reflectance Score (RS) was calculated using mean pixel values normalized between grayscale calibration standards. Articular cartilage thickness was measured at five random locations on each sample from images taken in the transverse orientation. Statistical analysis found no significant effect of limb side for either RS values or thickness, allowing data from right and left limbs to be grouped for analysis. There is a statistically significant correlation between joint region and thickness, as well as between joint region and RS; however, there was no statistical correlation between thickness and RS.

Objective: The purpose of this study was to evaluate the lifetime evolution of the radioclinical features in a large family with van Buchem disease., Design and Patients: The study population included 13 patients, ranging between 6 and 69 years. The evolution of the clinical features has been assessed by retrospective analysis of the clinical records of the patients. The age-related evolution of the cortical hyperostosis and defective modeling at the tubular bones was evaluated by morphometric analysis of hand films in 9 patients, compared with 9 control individuals. Progression of sclerosis of the craniofacial bones was evaluated by analysis of the skull radiographs of eleven van Buchem patients, taken at different age., Results and Conclusions: Radioclinical features, including sclerosis of the cranial and tubular bones and cranial nerve deficit, become more prominent in older patients. Defective modeling of tubular bones, cortical thickness and medullary width progress with age. Radioclinical abnormalities of van Buchem patients become more prominent in older patients, which suggests that the van Buchem gene is very actively involved in bone metabolism throughout life. Morphometric analysis of the plain films supports the hypothesis that the physiological function of the van Buchem gene is to inhibit bone formation and possibly to regulate bone remodeling.

Purpose: To determine the variability in the flexion/extension motion of the thumb metacarpophalangeal (MCP) joint in a normal volunteer population and to determine any correlation between the shape of the thumb metacarpal head, gender, age, thumb interphalangeal (IP) joint range of motion (ROM), and thumb MCP joint ROM in a population of fresh-frozen cadaver arms., Methods: The ROM of the thumb MCP joints of 100 volunteers (200 thumbs) was measured. The thumb MCP joints of 70 fresh-frozen cadaver arms were examined. Posteroanterior and lateral radiographs were taken of 64 MCP joints. Passive flexion and extension at the MCP and IP joints were measured with a standard goniometer starting at neutral (0 degrees ) with the metacarpal, proximal, and distal phalanges axially aligned. The distance from the volar to the dorsal edge of the articular surface (A) and the radius of curvature of the articular surface (r) of the metacarpal head were measured on the lateral view. The shape of the metacarpal head was given a value using the A/r ratio. Regression analysis was used to determine the correlation between the head shape and joint motion. The thumbs were categorized into a round group (A/r ratio > 1.7) or a flat group (A/r ratio of < 1.7) to facilitate statistical analysis., Results: The volunteer population mean thumb MCP maximum flexion was 77 degrees range, 40 degrees -126 degrees ). Range of motion in hyperextension varied from 0 degrees to 72 degrees, with a mean of 35 degrees. Total ROM was from 55 degrees to 176 degrees, with a mean of 110 degrees. In the cadaver population studied the average MCP joint ROM was 94 degrees (mean flexion, 70 degrees; mean extension, 24 degrees ). The A/r ratio had a range of 1.1 to 2.2. There were 37 round and 27 flat thumb metacarpal heads. Regression analysis showed a significant correlation between metacarpal head shape and ROM; MCP joints with rounder metacarpal heads had greater motion. Round and flat metacarpal heads had significantly different motion arcs averaging 106 degrees and 77 degrees, respectively. Female gender was associated both with significantly greater MCP joint ROM (99 degrees women/87 degrees men) and a significantly higher incidence of round metacarpal heads (66% of women/36% of men). No significant correlation existed between specimen age, MCP, and/or IP joint ROM., Conclusions: There is a wide range in the magnitude of the thumb MCP joint ROM and the normal shape (round vs flat) of the thumb metacarpal head. A rounder thumb metacarpal head has greater thumb MCP joint ROM than a flatter thumb metacarpal head. Clinically we have found this information helpful in predicting posttraumatic recovery of thumb MCP joint ROM and selecting candidates for and predicting patient satisfaction with thumb MCP joint arthrodesis.

Osteolysis syndromes are characterized by resorption of affected bones with associated swelling and pain. Various forms of multicentric osteolysis syndromes including autosomal dominant and recessive carpal-tarsal osteolysis, Torg, François, Whyte-Hemingway, Hajdu-Cheney, Winchester, and other forms have been described. Most present in pre-school years with extensive involvement and destruction of multiple bones. We present a sister-pair, both of whom presented in early teenage, i.e., 13 and 15.5 years, respectively, with bilateral ankle, knee, and later, wrist pain. Radiological examination revealed bilateral osteolysis of tali, scaphoids, and patellae, and short fourth metacarpals in both sisters. Further investigation revealed absence of renal involvement, a normal excretion of amino acids, mucopolysaccharides and oligosaccharides, and presence of chronic synovitis in both sisters. Both parents and a younger brother were without radiographic or clinical evidence of the disease and there was no history of consanguinity. Thus, our sister-pair presented with the same carpal and tarsal bone involvement at a much later age, with evidence of chronic synovitis, along with short fourth metacarpals (brachydactyly type E changes) and without renal disease, suggesting a new syndrome with probable autosomal recessive inheritance., (Copyright 2003 Wiley-Liss, Inc.)

Objective: In a 5-year followup study, we investigated the temporal relationship between development of wrist joint erosions as visualized by magnetic resonance imaging (MRI) versus conventional radiography (CR), in patients with rheumatoid arthritis. We also evaluated the risk of erosive progression on CR associated with the presence of MRI erosions., Methods: In 10 patients with rheumatoid arthritis, MRI and CR of the dominant wrist were performed annually for 5 years. In each image set, each wrist bone (metacarpal bases, carpal bones, radius, and ulna) was assessed for the absence or presence of bone erosions., Results: Nine bones showed radiographic erosions at baseline. Twenty-seven new radiographic erosions developed during the 5-year followup period. Of these 27 new erosions, 21 were detected 1-5 years earlier by MRI than by CR, 3 were simultaneously detected by both methods, 2 were detected 1-2 years later by MRI than by CR, and 1 erosion (radiographically detected at 5-year followup) was not visualized with MRI. MRI detection of new radiographic erosions preceded CR detection by a median of 2 years. In bones with MRI erosions at baseline, the relative risk of radiographic erosions at 5-year followup was 4.5 (95% confidence interval [95% CI] 2.6-7.6), compared with bones without baseline MRI erosions. If bones with baseline radiographic erosions were excluded from the analysis, the relative risk was 4.1 (95% CI 2.2-7.5)., Conclusion: Most new radiographic bone erosions (78%) were visualized at least 1 year earlier by MRI than by CR. This illustrates that the information on joint destruction provided by CR is considerably delayed compared with that provided by MRI. A significantly increased risk of progression of radiographic erosion in bones with baseline MRI erosions was observed, demonstrating a prognostic value of MRI with respect to long-term radiographic outcome.

Fractures of the hand are the most common fractures of the human skeleton. Metacarpal fractures account for 30% to 50% of all of hand fractures. The mechanisms of these injuries vary from axial loading forces to direct blows to the dorsal hand. Resulting deformities include malrotation, angulation, and shortening. Treatment modalities vary from nonoperative reduction to open reduction and internal fixation. The treatment algorithm is guided by the location of the fracture, the stability of the fracture, and the resultant deformity. Operative procedures, although they may lead to excellent radiographic reduction of fractures, often lead to debilitating stiffness from the inflammatory reaction of the surgical procedure. Operative fixation must be employed judiciously and offered only when confident that non-operative therapy can be improved on with operative intervention. This article reviews the various types of metacarpal fractures, with the treatment options available for each fracture. The indications for each treatment modality, postoperative care, and rehabilitation are presented.

A 27-year-old otherwise healthy patient was diagnosed with a primitive neuroectodermal tumor of the thumb metacarpal bone of the left hand. Based on a common chromosomal translocation this tumor shows a close relationship to Ewing's sarcoma. Its occurrence in the extremities is uncommon and involvement of the hand is extremely rare. The treatment consisted of neo- and adjuvant chemotherapy and marginal resection of the affected thumb metacarpal bone including periosseous soft tissue and reconstruction of the thumb by an intercalated segmental index pollicization.

Avascular necrosis of the metacarpal head is a rare condition. Although the condition is associated with trauma, systemic lupus erythematosus, and steroid use, it can occur spontaneously without any obvious cause. Any metacarpal may be affected and the pathologic changes are similar to those described in other bones such as the femur. The diagnosis requires an index of suspicion in a young patient with spontaneous onset of symptoms localized to a metacarpophalangeal joint. Magnetic resonance imaging is a useful early diagnostic tool when the radiographic findings are nonspecific or absent. The natural history of the condition is not known. Although symptoms may resolve with nonoperative treatment, progressive collapse of the metacarpal head and subsequent degenerative arthritis is a possible long-term outcome. Curettage of the lesion and supplementary cancellous bone grafting has been reported to provide symptomatic relief in cases resistant to nonoperative treatment. A case is presented of idiopathic avascular necrosis of the head of the dominant ring finger metacarpal in a 27-year-old woman. The purpose of this report is to highlight the clinical presentation, radiographic features, pathologic findings, and outcome at 2 years after curettage and bone grafting.

Bizarre parosteal osteochondromatous proliferation (BPOP) is a reactive lesion of cortical bone. A case of fifth metacarpal BPOP with intramedullary inflammatory extension is shown by magnetic resonance imaging. Histologically the intramedullary extension showed fibrosis with inflammatory cell infiltration. The surrounding adipose tissue showed fibrosis, focal inflammatory cell infiltration, and vascular proliferation. It is important to recognize that BPOP can bear radiologic resemblance to malignant lesions or osteomyelitis when there is an intramedullary inflammatory extension. Preservation of cortical bone under the osteocartilaginous mass on T1-weighted magnetic resonance imaging, and homogenous intramedullary enhancement with gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA), can be helpful for distinguishing BPOP from malignant lesions., (Copyright 2002 by the American Society for Surgery of the Hand)

Introduction: Trapeziometacarpal pre-arthrosis is a common condition with only limited therapeutic possibilities. Eaton and Littler designed a tendon stabilization., Materials and Methods: A series of 21 thumbs with painful carpometacarpal joints, treated with a ligament reconstruction according to Eaton and Littler, is described. Three failed and further surgery was required. The outcome of 18 is evaluated. There were 11 women, 7 men with a mean age of 33.7 years, all having stages I or II of osteoarthritis. Six (30%) had a traumatic event in their history., Results: In the early stages of degenerative osteoarthritis, the overall outcome was good with a mean DASH score of 23.2. The carpometacarpal joint was stable but a 43% progression of radiographic osteoarthritic deterioration of the joint occurred., Conclusion: Stabilization of a painful pre-arthritic trapeziometacarpal joint is useful and reliable. A traumatic instability had worse results and probably is a contraindication to this technique.

We report two cases of carpometacarpal dislocation of the four long fingers. They were diagnosed in emergency and treated by open reduction and stabilization by intramedullary pinning. They were followed for an average of 30 months. The results were rated good, and the two patients had an excellent grip strength, no deformity, no instability, no disabling or limited prehension. Dislocation or fracture-dislocation of the carpometacarpal joints are uncommon injuries. The diagnosis can be easily missed. The authors recommend closed or open reduction and fixation by pins and immobilisation in a plaster cast. The results was good in the two cases without complications.

Introduction: The main goal of first carpometacarpal arthritis surgical treatment is to relieve pain. The main disadvantages of the usual techniques (trapeziectomy, implant arthroplasty) are loss of strength or presence of a prosthetic device. It is difficult to propose such extensive surgery at an early stage of the disease. Selective denervation of the first carpometacarpal joint seems to be an interesting choice. We propose a new technique of denervation based on our previous anatomical investigations., Technique: Two incisions are needed to cut all the articular branches derive from the superficial branch of the radial nerve, the palmar cutaneous branch of the median nerve, the thenar branch of the median nerve and the lateral ante brachial cutaneous nerve., Material: Fourteen patients were prospectively included in our study with a mean follow-up of 5 months., Results: Pain relief was very satisfying in 12 cases (mean decrease 84%). An increase in grip and key pinch strength was noted. Complications were uncommon, excepted temporary paresthésia in the radial nerve area., Discussion: This technique seems to be promising and a good indication for patients with no disabling deformity, but only long-term results will confirm the place of denervation in the treatment of first carpometacarpal arthritis.

Our hypothesis was that post-yield mechanical behavior of compact bone material in compression, defined as the stress, strain, or energy absorbed between 0.2% strain-offset and the point of maximum stress, is correlated with material density, modulus, strength, histomorphometric evidence of remodeling, and post-failure gross specimen morphology. Post-yield behavior of compact bone material from the third metacarpal bone of 10 horses, ages 5 months to 20 years, was investigated using single-load compression-to-failure. The post-yield stress, strain, and absorbed energy were compared with the compressive elastic modulus, yield stress, ash density. post-failure macroscopic appearance of the specimen, and histologic evidence of remodeling. High values of elastic modulus, yield stress, and ash density were associated with low values of post-yield mechanical properties (stress, strain, and absorbed energy). Macroscopic post-failure morphology was associated with post-yield mechanical behavior, in that specimens displaying fractures were associated with lower post-yield mechanical properties, and that those without evidence of frank fracture were associated with higher post-yield mechanical properties. Microscopic evidence of remodeling activity was associated with high post-yield mechanical properties, but not with gross post-failure morphology. There was an abrupt change from relatively high values to extremely low values of post-yield mechanical properties at intermediate levels of ash density. This feature may serve as a functional tipper limit to the maximization of bone material stiffness and strength.

Volar dislocation of the carpometacarpal joint of the little finger is an uncommon injury. It is subdivided in ulnopalmar and radiopalmar dislocations. The injury can easily be missed on standard x-rays. Closed reduction and K-wire fixation has commonly been used in the treatment, although closed reduction and casting has been reported. Only 10 cases of an ulnopalmar dislocation were published previously. We report a case of a simultaneous dislocation of the 4th metacarpophalangeal joint and an ulnopalmar dislocation of the 5th carpometacarpal joint. The combination of these injuries has not been reported yet. We review the available literature and discuss the methods of treatment.

Aneurysmal bone cysts of the hand skeleton are rare (only 3 to 4 % of all ABC; Tillmann and v. Torklus 1966 ) and require a differentiated treatment. In the presented case, the fourth metacarpal bone of the right hand was affected (Enneking stage 3). On account of its rapid growth, radical excision was performed and the resected metacarpal bone was replaced by a bicortical iliac crest graft. The bone graft healed in without complications, the functional result is satisfactory. On twelve-month follow-up there were no signs of relapse.

Treatment of the first web injuries are based on the concept of one stage repair of the complex injuries of the hand with early motion. Radical debridement is specially important in case of muscular attrition. Fasciotomie of the first web is systematic in case of crush injuries for avoiding compartimental syndrome. For prevention of first web retraction, one or two Kirchner wires are placed in emergency between first and second metacarpal, and later a spilt in maximal anti-position of the first ray. In case of communited fractures, skeletal stabilisation use inlay internal devices, such the blocked intramedullary nail. First web reconstruction must take into consideration the cutaneous functionnal units of the hand, described by Michon. Thin and split-thickness grafts are rarely used for covering skin defects of the first web space, because their ability of retraction. Exposition of bone or tendons leads to the realisation of a flap. Soft tissue coverage must be achieved in emergency or after a second look within the first 48 hours. The kite flap is the most useful local flap for the first web space. The interosseous flap is the best choice among the regional pedicled flap. The use of the Chinese flap must be very careful, because the possibility of contusion of the radial pedicle in these types of injuries. It is only in case of contra-indication of the interosseous flap that free flaps can be realised, as the lateral arm flap or the parascapular flap. The groin flap keeps few indications for aesthetic reasons, or when regional flaps and microsurgery are contra-indicated.

Eumycetoma is a mycotic disease caused by saprophytic soil fungi that are usually inoculated through minor injuries. A case of mycetoma in a Brazilian farmer aged 71 years is reported. This patient presented erythema and edema on the dorsal surface of the left hand with multiple crusted and cicatricial lesions. No macroscopic grains were observed. The histopathological findings showed grains consisted of numerous hyphae which stained well with Gomori-Grocott method. This material obtained by cutaneous biopsy was submitted to culture on Sabouraud's medium and the colonies were identified as Fusarium solani. The radiological studies revealed bone osteolytic lesions and the ultrasound showed pseudocysts and fistulae at the site of this infection. The patient was treated with oral ketoconazole with a good clinical response.

We present a case of osteoid osteoma of the right third metacarpal bone in a 23-year-old man. He had an apparent history of initial injury, followed by pain and swelling. He was initially treated for post-traumatic periostosteitis, so that the diagnosis of osteoid osteoma was delayed. Computed tomography and histology confirmed the latter diagnosis. En bloc resection of the nidus was followed by complete resolution of his symptoms. This case report emphasises the difficulties in diagnosis, particularly after an injury, and illustrates its effective treatment.

Juvenile aponeurotic fibroma is a rare benign tumour which occurs mainly in young patients under 20 years of age and especially during childhood. Clinical presentation is a unique, hard and painless tumour of the palm or sole. The treatment commonly accepted for this locally recurrent tumour is complete excision with function preservation. In this paper, we report on a case of juvenile aponeurotic fibroma of the thenar area with a thickening of the first metacarpal bone shaft. Bone involvement in juvenile aponeurotic fibroma is a very rare condition. We only found one report of a comparable case in literature.

Metastatic tumours of the hand are uncommon. The majority of these tumours affect the phalanges and the primary tumours are usually bronchogenic in origin, with breast and kidney tumours next in frequency. Metastatic gastrointestinal to the hand is rare and usually from the colon. We report a case of poorly differentiated adenocarcinoma of the stomach antrum presenting with a metastatic lesion to the right 4th metacarpal bone. A review of the literature is included.

This report describes a chondromyxoid fibroma which developed in the distal part of the second metacarpal of a 12-year-old girl. The tumor is rare, perhaps the rarest of all bone tumors, and the occurrence in a metacarpal of a young female is extraordinarily uncommon.

Hypertrophic osteoarthropathy (HOA) typically occurs concurrently with clubbing of the digits, with isolated HOA being reported only rarely. We report two patients with intra-thoracic malignancy in whom HOA, demonstrated on bone scintigraphy, developed in the absence of clubbing. We also report the novel observation of involvement of the metatarsal and metacarpal bones by HOA.

Intraosseous ganglia occur most frequently in the long bones of the lower limbs, particularly in the medial malleolus of the tibia. They usually appear as radiographically well circumscribed juxta-articular cystic lesions, containing myxoid fibrous tissue histologically. Intraosseous ganglia in the hand are very rare. Most reported cases have involved the carpal bones, in particular the lunate and scaphoid. To our knowledge, the present case is the third report of an intraosseous ganglion appearing in the first metacarpal bone; it arose in a patient who had been on dialysis for 25 years, mimicking amyloidosis of bone.

The effect of gastrointestinal nematode infections on bone development was investigated in growing sheep on pasture. Forty-five weaned lambs from six groups in a two-factorial design incorporating stocking rate (SR; low, medium and high) and presence or absence of infection on pasture were sampled in the late grazing season. Worm counts were performed at slaughter, and the left metacarpal bones were excised for bone assessment. Faecal egg counts and worm burdens, primarily of Ostertagia circumcincta and Trichostrongylus vitrinus, were considerably higher in the high SR infected group ("I-High") than in comparable animals at low or medium SRs, whereas uninfected groups showed negligible egg excretion. Clinical biochemistry revealed significantly reduced serum concentrations of albumin, calcium and alkaline phosphatase in infected lambs. Nematode infections were associated with significant reductions in bone mineral density (30% at high SR), measured by dual energy X-ray absorptiometry, and in bone size (9%). Histomorphometry indicated thinning of the trabecular structure and reduced bone formation in the infected groups, particularly the I-High group. Bone mineral density, bone tissue volume and structural changes were strongly associated with log-transformed worm counts. The study showed that lambs suffering from moderate to heavy degrees of naturally acquired gastrointestinal nematode infection developed marked osteopenia after weaning, i.eduring the later part of the grazing season., (Copyright Harcourt Publishers Ltd.)

A case of compression of the deep branch of the ulnar nerve associated with pseudarthrosis of the base of the fifth metacarpal and the upper shaft of the fourth metacarpal is reported. The delayed procedure consisted in volar decompression of the ulnar nerve by dividing the pisi-hamate ligament and plating and grafting of both fractures. The patient achieved marked improvement four weeks post-operatively and had complete functional recovery at follow-up of 16 years after injury without narrowing of the hamato-metacarpal joint despite synostosis of the bases of the medial metacarpals.

Function preserving management of a dominant thumb metacarpal chondrosarcoma is reported, with a literature review for this uncommon neoplasm. Wide local excision of the metacarpal followed by temporary silicone block interposition and definitive iliac crest bone grafting was performed. A persistent wound defect was managed by a radial artery forearm flap. The functional result was acceptable. In the literature, there were seven cases of thumb metacarpal chondrosarcoma reported; two were treated by ray amputation, and the other five were treated by excision of the metacarpal. Three of those five had bone graft and the other two had simple resection. Of these seven cases, three had local recurrence and one a distant metastasis.

The authors report a case of non-traumatic avascular necrosis of the third metacarpal head. This very rare condition is known as Dieterich's disease and has been associated with trauma, systemic lupus erythematosus and steroid use.

The densitometric and mechanical structural properties of the left and right fifth metacarpal bones of 10 racing greyhounds with a fracture of the central tarsal bone and 10 without a fracture were investigated by dual energy x-ray absorptiometry and a servo-hydraulic materials testing machine. In all the greyhounds the bone mineral density of the left fifth metacarpal bone was significantly greater than that of the right (P<0.001), but there was no significant difference between the degree of asymmetry in bone mineral density in the two groups. The ultimate torque and energy-to-failure of the left fifth metacarpal bone of the greyhounds with a fracture of the right central tarsal bone were significantly higher than in the right fifth metacarpal bone and higher than in both the left and right fifth metacarpal bones of the greyhounds with no fracture (P<0.05). The ultimate torque and energy-to-failure were significantly related to bone mineral density (P<0.005), and 22 per cent of the variation in these structural properties could be explained by variations in bone mineral density. Fifth metacarpal remodelling in response to asymmetric cyclic loading is bone-specific, and structural properties are enhanced in the left fifth metacarpal of greyhounds with a fracture of the right central tarsal bone.

Two sisters born to consanguineous Lebanese parents had mental retardation and epilepsy, brachymetacarpalia, hirsutism, bulbous soft nose, thick floppy ears with abnormal configuration and gingival hypertrophy. One girl presented additionally with tetralogy of Fallot and the other with congenital hypothyroidism and bilateral ureteral stenosis. These manifestations resemble the syndrome of hypertrichosis-gingival fibromatosis-mental retardation and seizures of Anavi et al. [1989: Dev Med Child Neurol 31:538-542] but our two girls additionally have brachymetacarpia. The inheritance seems to be autosomal recessive. These two sisters may represent a hitherto undescribed syndrome. We discuss the findings in our patients in relation to the literature., (Copyright 2000 Wiley-Liss, Inc.)

Objective: To report the clinicopathologic features of solitary skeletal hemangioma of the extremities and to review previous cases in the English language medical literature., Patients: In addition to five of our own cases, 34 literature cases with substantial and 75 with partial clinicopathologic information were found., Results: Our patients, three men and two women, ranged in age from 37 to 83 years (mean 65.6 years). The lesion was an incidental radiologic finding in two patients, while three were symptomatic. In no case was a correct preoperative radiologic diagnosis made, a malignant process being considered as a possibility in all. The hemangiomas were medullary; two involved a metacarpal, two the fibula, and one the humerus. In contrast, previously reported patients were younger (mean age 32 years), predominantly female (60%), and symptomatic in over 90% of cases. The lesion is rare in those younger than age 10 years or older than age 60 years. As in our patients, the long bones are most frequently involved (75%), with the diaphysis or metadiaphysis, as in four of our patients, the most common locations. Although 20% of cases occur in the hands or feet, metacarpal involvement is rare. Medullary origin, as in all of our cases, is most frequent, but 45% of cases are either periosteal (33%) or intracortical (12%). In the literature, cavernous hemangioma is the most frequent type. Three of our hemangiomas were cavernous, one capillary, and one venous, the latter being rarely reported in extremity bones., Conclusions: Due to the diversity of radiologic patterns produced by skeletal hemangioma, a correct preoperative diagnosis is rarely made. Almost all patients do well, even those with less than complete removal of the lesion; local recurrence is rare. All of our patients were well following either therapeutic or simple diagnostic procedures. Due to the destructive nature of some biopsy procedures, the histologic diagnosis of hemangioma may at times also be problematic.

Giant cell tumor is among the rare tumors of the bone. We present a case of metacarpal giant cell tumor with radiographic, computed tomographic (CT) and histologic findings, as well as grey scale and Doppler sonographic features. We also present the "doughnut"-shaped appearance on scintigraphy of the lesion, which has not been shown on a metacarpal giant cell tumor.

Background: Giant cell tumor of the small bones of the hand and foot is suspected of having some peculiar features compared with giant cell tumor in other sites. Moreover, it could share some features with other giant cell rich lesions involving the hand and foot, and this may affect the differential diagnosis. The aim of this study was to analyze the features of lesions such as these in the files of the Rizzoli Orthopedic Institute., Methods: The incidence of giant cell tumors of the bones of the hand and foot seen at the Rizzoli Orthopedic Institute over 50 years (1947-1997) was taken into consideration. There were 8 lesions of the hand and 21 of the foot. Clinical information and follow-up of the patients were studied and updated. Radiographs were studied and radiographic features analyzed. Histopathologic material was thoroughly reviewed and histologic features analyzed., Results: Although the location of tumor was helpful information, radiographic features were not specific. Giant cell tumors of the small bones of the hand and foot showed a predominance in females, younger patients and more aggressive behavior than giant cell tumors of large bones. The authors did not observe multicentricity or pulmonary metastases., Conclusions: Because the radiographic features of giant cell tumor of the hand and foot overlap those of other giant cell rich lesions in these locations, histologic diagnosis is mandatory, although it may be difficult and require the establishment of diagnostic criteria for giant cell tumor. As this tumor tends to be more aggressive than other giant cell rich lesions, treatments of choice are aggressive curettage or resection.

Intraosseous schwannoma (neurilemmoma) is an extremely rare, benign neoplasm, constituting less than 0.2% of primary bone tumors. It infrequently involves the bones of the hand. We present a case of intraosseous neurilemmoma of the metacarpal.

We report here three fully documented cases of periosteal chondroma diagnosed and treated in our hospital. There have been few references since Lichtenstein first described this condition as a separate tumour, and none of them concerned children under 10 years old. deSantos accurately describes the radiological features of the tumour. All of our patients were under 10 years old at the moment of the appearance of the lesion, which was always detected in the long bones of the upper limbs. The study included a previous histological examination in two cases and a follow-up in all of them. From this study we learned that invasive diagnosis procedures are unnecessary as we could follow the behaviour and evolution of this cartilaginous benign tumour for a long period of time.

We report a case in which an autogenous periosteal autograft was used to resurface a large osteochondral defect in the thumb carpometacarpal joint of a young woman. Good results were found at 4-year follow-up examination.

A patient with multiply recurrent giant cell reparative granuloma of the third metacarpal is reported. Three prior excisions failed to prevent recurrence. A wide resection and replacement with a nonvascularized fibular bone graft resulted in elimination of the tumor at the 7-year follow-up visit.

Extra-abdominal desmoid tumor of the hand is rare and only 10 cases have been described in the literature. We present a 14-year-old boy with a recurrent extra-abdominal desmoid tumor in the dorsal site of the right hand. MR image demonstrated the tumor in the third dorsal interosseous muscle, and adhered to the radial side of the forth metacarpal bone. The lesion revealed iso-signal intensity on T1-weighted images and high intensity on T2. We performed a marginal excision. Histological examination of the tumor showed proliferation of the fibroblastic cells with abundant collagen bundles. He developed local recurrence for the third time. The size of the third recurrent tumor has not been changed for 2 years and 3 months. Therefore, we have not performed any additional surgery. Since extensive resection markedly diminishes the function of the hand, we consider that a marginal surgical margin is acceptable for the quality of daily life of patients with a desmoid tumor of the hand.

An 8-mo-old captive male reticulated giraffe (Giraffa camelopardalis reticulata) developed an acute lameness (grade IV/V) of the right forelimb, with swelling of the metacarpophalangeal joint. A traumatic injury was suspected based on clinical, radiographic, and arthroscopic evaluation. Several abnormalities were identified arthroscopically, including synovitis, cartilage damage, and an osteochondral fragment. Medial collateral ligament damage was also suspected based on radiographic evaluation. Arthroscopy provided a means of diagnosis and treatment of the abnormalities identified. The lameness in this giraffe resolved within 6 wk following arthroscopic surgery.

Foreign bodies within soft tissues are common in children. They may cause a chronic inflammatory reaction that can result in abnormal findings on radiographs, including lytic or blastic osseous changes. These radiographic findings can mimic both benign and malignant processes. In cases where the history is uncertain and the foreign body is not recognized, magnetic resonance (MR) imaging can make a specific diagnosis and direct appropriate therapy.

Osteonecrosis of the metacarpal is rare. Previously reported cases have only involved the metacarpal heads, with the long finger being the most commonly affected. We present a patient with avascular necrosis involving the base of the second metacarpal.

The use of metacarpal dimensions for determining skeletal sex is investigated. Previous studies on sexual dimorphism in the metacarpals (Scheuer and Elkington [1993]; J. Forensic Sci. 38:769-778; Falsetti [1995]; J. Forensic Sci. 40:774-776; Smith [1996]; J. Forensic Sci. 41:469-477) used multiple variables, which limits the application potential of the methodology. Using six measurements for each metacarpal, I generated 35 linear discriminant functions based on expected taphonomic or pathological preservation scenarios. The number of variables per function ranged from 2-5. Normal, jackknifed, and cross-validation classification matrices indicated a sex prediction accuracy in the 79-85% range. MC4 produced the most consistent functions. Overall accuracy in the validation samples ranged from 75-90%. ANOVA and MANOVA analyses indicated that population effects are insignificant, which may allow for the application of the functions without knowledge of the ancestral background of the individual. This, combined with the variety of preservation scenarios considered, provides accurate sex estimators for incomplete individuals. However, the population specificity of the insignificant population group effects remains untested.

Five cases of acquired flexural deformity of the metacarpophalangeal joint (MCPJ) in older horses and ponies were studied. The mean age of affected horses was 14-8 years. Four deformities developed following desmitis of the accessory ligament of the deep digital flexor tendon (ALDDFT) and superficial digital flexor tendon (SDFT) and one following tendonitis of the SDFT alone. All cases were markedly lame and demonstrated variable degrees of flexural deformity. Ultrasonographic examination was performed on all cases which revealed extensive adhesion formation between the ALDDFT and SDFT and reduced cross-sectional area of the deep digital flexor tendon in each case. A variety of treatments were unsuccessfully employed to treat this condition. The prognosis for acquired flexural deformity of the MCPJ in old horses following tendonous damage in the palmar metacarpus is likely to be poor.

Osteoid osteoma is a benign primary tumour of bone occurring in the first two decades of life. It presents with pain and is uncommon in the hand, particularly so in the metacarpals. We report a painless osteoid osteoma affecting a metacarpal.