The prognosis for return to athletic function for Thoroughbred racehorses in Hong Kong with injuries to the palmaroproximal aspect of the metacarpus diagnosed using low-field magnetic resonance imaging

OBJECTIVE

To evaluate and compare the prognosis for Thoroughbred racehorses to return to galloping and racing with injuries to the palmaroproximal metacarpus diagnosed with MRI.

ANIMALS

29 flat racing Thoroughbreds at the Hong Kong Jockey Club that underwent MRI between 2014 and 2022.

METHODS

Clinical, radiographic, ultrasonographic, and MRI reports were collected from veterinary clinical records, and these were combined with training and racing data. Horses were categorized on the basis of MRI diagnosis: (1) proximal suspensory ligament (PSL) involvement only, (2) PSL and concurrent proximal third metacarpal (MC3) bone involvement, and (3) proximal MC3 bone involvement only. The following were compared for prognosis for return to athletic function: return to galloping or racing, and reinjury.

RESULTS

Overall, the prognosis for return to athletic function was fair, with 92% (22/24; P = .53) and 67% (16/24; P = .73) of horses returning to galloping and racing, respectively. There was a relatively low reinjury rate, with 18% (4/22) of horses reinjuring. Horses with concurrent injury to both the PSL and proximal MC3 bone (Category 2) took longer to return to gallop (median, 116; IQR, 100.5 to 160), when compared with horses having only PSL injury (median, 69; IQR, 43 to 80; P = .04). Of the 4 horses that reinjured, 3 (75%) were horses in Category 2.

CLINICAL RELEVANCE

The findings from this study suggest that injuries involving both PSL and proximal MC3 bone concurrently require a longer rehabilitation period than those with PSL involvement alone.

Positron emission tomography assessment of metacarpal/metatarsal condylar fractures post surgical repair: Prospective study in 14 racehorses

OBJECTIVES

To assess 18F-sodium fluoride (18F-NaF) positron emission tomography (PET) findings associated with metacarpal/metatarsal condylar fractures at the time of fracture repair and through healing.

STUDY DESIGN

Prospective descriptive study.

ANIMALS

Fourteen Thoroughbred racehorses.

METHODS

18F-NaF PET was performed within 4 days of surgical metacarpal/metatarsal condylar fracture repair, on both the injured and contralateral limb. Follow-up PET scans were offered at 3- and 5-months post fracture repair. Areas of abnormal uptake were assessed using a previously validated grading system.

RESULTS

Eight fractures were located in the parasagittal groove (PSG) (six lateral and two medial) and six fractures were located abaxial to the PSG (non-PSG) through the palmar/plantar condyle (all lateral). All horses in the latter group had uptake in the lateral palmar condyle of the contralateral limb suggestive of stress remodeling. Three horses with PSG fractures had uptake in a similar location in the contralateral limb. Horses with lateral condylar fracture only presented minimal or mild uptake in the medial condyle, which is considered atypical in the front limbs for horses in full training. Four horses developed periarticular uptake in the postoperative period suggestive of degenerative joint disease, three of these horses had persistent uptake at the fracture site. These four horses did not return to racing successfully.

CONCLUSION

The findings of this study provide evidence of pre-existing lesions and specific uptake patterns in racehorses suffering from metacarpal/metatarsal condylar fractures.

CLINICAL SIGNIFICANCE

PET has a possible role in the prevention, diagnosis, and postoperative monitoring of metacarpal/metatarsal condylar fractures in racehorses.

Current management of avascular necrosis of the metacarpal head: a comprehensive literature review

BACKGROUND

Avascular necrosis (AVN) of the metacarpal head is a rare disease that may lead to progressive destruction of the metacarpophalangeal joint and hand function. This study aimed to describe the epidemiology, possible risk factors, clinical presentation, diagnostic workup, and treatment of the rare condition of avascular necrosis of the metacarpal head.

METHODS

Articles were searched using the subject words "Dieterich disease","Mauclaire's disease", and "avascular necrosis of metacarpal head" in the PubMed and Scopus databases. Studies were retained for review after meeting the inclusion criteria. Those outcomes relevant to diagnose and assessing AVN of the metacarpal head and those related to curative management were extracted.

RESULTS

The literature search revealed 45 studies with 55 patients. Although the aetiology of osteonecrosis has not been clearly delineated, AVN of the metacarpal head most commonly arises from trauma but other risk factors may also be involved. Plain radiographs are often negative and therefore likely to be missed. Early-stage osteonecrosis of the metacarpal head was best assessed using MRI. Given the rarity of this condition, there is no clear consensus on the treatment.

CONCLUSIONS

Avascular necrosis of the metacarpal head should be considered in the differential diagnosis of painful metacarpophalangeal joints. An early understanding of this unusual disease will provide an optimal clinical outcome, restoring joint activity, and resolving pain. Nonoperative treatment cannot cure all patients. Surgical management is based on the patient and lesion characteristics.

Influence of a novel scaffold composed of polyurethane, hydroxyapatite, and decellularized bone particles on the healing of fourth metacarpal defects in mares

OBJECTIVE

To determine the effect of a novel scaffold, designed for use in bone regeneration, on healing of splint bone segmental defects in mares.

STUDY DESIGN

In vivo experimental study.

SAMPLE POPULATION

Five adult mares (4-10 years old; mean weight, 437.7 kg ± 29 kg).

METHODS

Bilateral 2-cm full-thickness defects were created in the fourth metacarpal bones (MCIV) of each horse. Each defect was randomly assigned to either a novel scaffold treatment (n = 5) or an untreated control (n = 5). The scaffold was composed of polyurethane, hydroxyapatite, and decellularized bone particles. Bone healing was assessed for a period of 60 days by thermography, ultrasonography, radiography, and computed tomography (CT). Biopsies of each defect were performed 60 days after surgery for histological evaluation.

RESULTS

On the basis of radiographic analysis, scaffold-treated defects had greater filling (67.42% ± 26.7%) compared with untreated defects (35.88% ± 32.7%; P = .006). After 60 days, CT revealed that the density of the defects treated with the scaffolds (807.80 ± 129.6 Hounsfield units [HU]) was greater than density of the untreated defects (464.80 ± 81.3 HU; P = .004). Evaluation of histology slides provided evidence of bone formation within an average of 9.43% ± 3.7% of the cross-sectional area of scaffolds in contrast to unfilled defects in which connective tissue was predominant throughout the biopsy specimens.

CONCLUSION

The novel scaffold was biocompatible and supported bone formation within the MCIV segmental defects.

CLINICAL SIGNIFICANCE

This novel scaffold offers an effective option for filling bone voids in horses when support of bone healing is indicated.

Reproducibility of Metacarpal Bone Mineral Density Measurements Obtained by Dual-Energy X-Ray Absorptiometry in Healthy Volunteers and Patients With Early Arthritis

Reduction in cortical bone mineral density at diaphysis of metacarpal bones of the hand, evaluated by dual X-ray radiogrammetry, has a bad prognostic value in patients with early arthritis. Nevertheless, this technique is hardly accessible in clinical practice. By contrast, evaluation of cortical bone mineral density at that location has not been previously assessed by conventional dual X-ray absorptiometry. The aim of this study is to evaluate the reproducibility of bone mineral density measurements at diaphysis of metacarpal bones using conventional dual X-ray densitometry in a population of healthy volunteers and patients with early arthritis. Nondominant hand dual X-ray densitometry was performed at three consecutive times with complete hand replacement in 27 subjects: 10 early arthritis and 17 healthy volunteers. Three different evaluators analyzed the 3 measurements of second to fourth metacarpal bones. To assess the reproducibility and accuracy of the measurements, intra- and interobserver agreement degrees, intra- and interclass correlation coefficients, smallest difference detectable assessment, and Bland Altman graphs were calculated. The coefficients of variation obtained for the different metacarpal evaluations were 2.25%, 2.91%, 2.85%, and 2.07% for metacarpal-2, metacarpal-3, metacarpal-4, and mean metacarpal-second to fourth, respectively, with a smallest difference detectable of 0.028, 0.034, 0.028, and 0.03 g/cm², respectively. The mean intra- and interobserver correlation coefficients between of metacarpal second to fourth were 0.990 (95% confidence interval [CI]: 0.982-0.995) and 0.995 (95% CI: 0.991-0.997), respectively. As expected, women had lower bone mineral density at metacarpal bones, especially after menopause. The results obtained in this study show an excellent reproducibility of bone mineral density measurements at diaphysis of metacarpal bones of the hand, measured by conventional dual X-ray densitometry, in a mixed population of healthy subjects and patients with early arthritis. This is of great interest for longitudinal studies in patients with early arthritis.

Effect of rheumatoid arthritis and age on metacarpal bone shaft geometry and density: A longitudinal pQCT study in postmenopausal women

OBJECTIVE

This study aimed to elucidate the effects of changes in the geometry and density of the metacarpal bone of patients with rheumatoid arthritis (RA).

METHODS

This prospective study included consecutive postmenopausal RA patients who met the American College of Rheumatology Criteria and healthy controls (HC). Peripheral quantitative computed tomography scans at 50% of the total metacarpal shaft (third metacarpal bone) were obtained at baseline and follow-ups. Use of bisphosphonates (BP), glucocorticoids (GC), biologics, and disease-modifying anti-rheumatic drugs (DMARD) was monitored (baseline to follow-up). Total cross-sectional area (CSA), cortical-transitional zone and compact zone CSA, cortical volumetric bone mineral density, and compact cortex porosity were measured. A linear mixed-effects model was used to determine significant differences in the rate of change in the RA and control groups and in RA patient subgroups.

RESULTS

Thirty-nine RA patients and 42 consecutive postmenopausal HC were followed for 63 months. RA and HC depicted a time-dependent increase of medullary CSA (+0.41 mm²/year, P < 0.0001), while total CSA remained stable (P = 0.2). RA status was associated with a loss of cortical bone mineral density (interaction: -3.08 mg/mm³; P = 0.014). In RA subgroup analysis, GC use ≥5 mg/day was positively correlated with a fourfold increase of medullary CSA (0.67 mm²/year P = 0.009), which resulted in a three- to fourfold loss of cortical density (-6.6 mg/mm³/year; P = 0.002) and cortical CSA (-0.57 mm²/year, P = 0.004). Patients with high disease activity and high GC dose at baseline demonstrated an increase in the total CSA (0.29 mm²/y; P = 0.049) and a loss of cortical BMD (-5.73 mg/mm³/y; P = 0.05) despite good clinical response.

CONCLUSION

Increase in medullary metacarpal CSA and thinning of the cortical CSA are physiological and time dependent. RA status is associated with loss in cortical density. Even upon biological therapy, low glucocorticoid dose affects metacarpal bone shaft geometry and density over time.

Metacarpal Aneurysmal Bone Cyst En Bloc Resection Reconstructed With Osteoarticular Allograft

Aneurysmal bone cysts are large lytic lesions that appear most often around metaphyseal bone. The lesions are locally aggressive with high recurrence rates. Therefore, wide resection is commonly necessary, leading to challenging reconstruction of the defect, especially when the articular surface is involved. We present a case of an aneurysmal bone cyst of the fourth metacarpal, treated with an en bloc resection and reconstruction with a metacarpal osteoarticular allograft. At 8 years after surgery, the patient has shown no signs of recurrence, but radiographic articular reabsorption was noted. However, the patient showed an excellent outcome with a satisfactory active range of motion and grip strength. Despite potential complications, osteoarticular allograft is a feasible alternative when autologous osteoarticular reconstruction is not an option.

Association of catastrophic condylar fracture with bony changes of the third metacarpal bone identified by use of standing magnetic resonance imaging in forelimbs from cadavers of Thoroughbred racehorses in the United States

OBJECTIVE To compare bony changes of the third metacarpal bone (MC3) of Thoroughbred racehorse cadavers with (cases) or without (controls) catastrophic condylar fracture by use of standing MRI. SAMPLE 140 forelimbs from 26 case horses (both forelimbs) and 88 control horses (single forelimb). PROCEDURES Bone marrow lesions (BMLs), identified as a decrease in T1-weighted (T1W) signal and increases in T2*-weighted (T2*W) and short tau inversion recovery (STIR) signals, and dense bone volume percentage (DBVP), identified as decreases in T1W, T2*W, and STIR signals, in the distopalmar aspect of MC3 were recorded. Logistic regression was used to compare fractured and nonfractured limbs of cases and fractured limbs of cases with randomly selected limbs of controls. RESULTS Among cases, fractured limbs were significantly more likely to have BMLs (26/26 [100%]) than were nonfractured limbs (7/26 [27%]). Fractured limbs of cases were significantly more likely to have BMLs (26/26 [100%]) than were limbs of controls (6/88 [7%]). Among cases, there was no significant difference in DBVP between fractured and nonfractured limbs in lateral (26% vs 21%, respectively) or medial (25% vs 20%, respectively) condyles. However, DBVP was significantly greater in fractured limbs of cases than in limbs of controls for lateral (26% vs 16%, respectively) and medial (25% vs 18%, respectively) condyles. CONCLUSIONS AND CLINICAL RELEVANCE Standing MRI revealed a significantly greater degree of bone change in racehorses with condylar fracture when comparing fractured and nonfractured limbs of case horses and fractured limbs of case horses with randomly selected limbs of control horses.

Long-term Outcomes of Partial Trapeziectomy With Capsular Interposition Arthroplasty for Osteoarthritis of the Thumb Basal Joint

The purpose of this study was to describe long-term outcomes of partial trapeziectomy with capsular interposition (PTCI) arthroplasty for patients with osteoarthritis of the basal joint of the thumb. A total of 27 patients (20 women, 7 men; 32 thumbs) with a mean age of 61 years (range, 47-74 years) agreed to return for follow-up and were included in the study. Mean postoperative follow-up was 64.3 months (range, 28-112 months). Evaluation included tests for grip and pinch strength; range of motion of the metacarpophalangeal joint; measurement of the first web space; completion of the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire; visual analog scale (VAS) measurements; and radiographic examination of the hand. A paired, 2-tailed t test was used to determine statistical significance (P<.05) of pre- and postoperative values. Postoperative values for grip strength were significantly increased from preoperative values. No significant loss of pinch strength was noted. Excessive hyperextension of the metacarpophalangeal joint did not occur, and the first web space was maintained. The mean DASH questionnaire and VAS scores were 5.06 (range, 0-26.5) and 0.32, respectively. Use of PTCI arthroplasty resulted in minimal loss in thumb height (7%) and significantly reduced thumb metacarpal subluxation (13%). There were no reported complications. The low DASH questionnaire and VAS scores compare well with other studies and indicate good functional outcomes. In treating thumb basal joint osteoarthritis, use of PTCI arthroplasty may result in improved thumb stability and grip strength, minimal subsidence of the thumb metacarpal, and reduced joint subluxation. [Orthopedics. 2018; 41(2):e228-e233.].

A case of Riley Ruvalcaba syndrome with a novel PTEN mutation accompanied by diffuse testicular microlithiasis and precocious puberty

BACKGROUND

Bannayan Riley Ruvalcaba syndrome (BRRS) is exceedingly rare, with only about 50 reported cases to date.

CASE PRESENTATION

We report a patient with hypoglycemia, precocious puberty and diffuse testicular microlithiasis accompanying BRRS, and think that this case is important in the light of a newly identified mutation in the PTEN gene.

CONCLUSIONS

Close attention must be paid in terms of PTEN mutations in cases of macrocephaly and accompanying neurological and dermatological findings.

Intrarticular injections of hyaluronic acid for trapezio-metacarpal osteoarthritis: a systematic review

Osteoarthritis (OA) of the base of the thumb, also known as Trapezio-Metacarpal (TM) OA, is a disabling condition, which mainly affects women and manual workers. When TM OA is not adequately treated, patients develop deformity and loss of function of the thumb. The surgical approach is a widespread strategy to treat this condition, but there is still no consensus on the most effective procedure. Therefore, several conservative strategies are commonly used, such as nonsteroidal anti-inflammatory drugs (NSAIDs) administration, thumb strengthening exercise, splinting, steroid (CS) and hyaluronic acid (HA) intrarticular injections. The present review of the literature aims to summarize the available scientific evidence on the treatment of TM OA with injections of HA. Thirteen studies were included: 7 randomized controlled trials, 5 case series and a case-control study. Among these, 5 studies compared HA versus CS injection. Results from most of them reported better outcomes with HA injections in terms of function (strength) and joint motion, while CS injections had greater effect on pain; moreover, CS action was faster but shorter, while HA required more time to obtain a therapeutic benefit and lasted longer. In non-comparative articles, this trend was also confirmed. Indeed, the authors reported an improvement in pain relief up to six months. Similarly, all studies indicated hand function improvement over time, measured though DASH score, pincher and grip strength tests. Available data from included studies show that there is no clear evidence to suggest a treatment with HA injections as the best advisable non-operative treatment for TM OA. However, promising potentials were shown by the randomized controlled trials, suggesting that there is some benefit and less comorbidities with the administration of HA. Further research, such as trials evaluating larger cohorts with validated scores for long-term follow-up, is still necessary.

Histologic and immunohistochemical evaluation of biocompatibility of castor oil polyurethane polymer with calcium carbonate in equine bone tissue

OBJECTIVE To evaluate the efficacy of castor oil polyurethane polymer with calcium carbonate for use in a unicortical ostectomy on the dorsal surface of the third metacarpal bone of horses. ANIMALS 6 adult horses. PROCEDURES A unicortical ostectomy was created on the dorsal surface of both third metacarpal bones of each horse. Castor bean (Ricinus communis) oil polyurethane polymer with calcium carbonate was implanted into the ostectomy on 1 limb, and the ostectomy of the contralateral limb was left unfilled and served as a control sample. Ostectomy sites were evaluated histologically 120 days later. Biopsy specimens were obtained from the interface of bone and polymer or the interface of bone and newly formed tissue; specimens were processed for histomorphometric evaluation by use of light microscopy, immunohistochemical analysis, histochemical analysis, and transmission electron microscopy. RESULTS Osteoconductive activity of the biomaterial was confirmed by the presence of osteoblasts in the biopsy specimens. Absence of a chronic inflammatory response or foreign body reaction indicated biocompatibility. Expression of osteoblast markers was detected in the newly formed tissue. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that castor oil polyurethane polymer with calcium carbonate could be an acceptable compound for use as a bone substitute in horses with fractures in which bone filling is necessary.

Digital X-ray radiogrammetry and its sensitivity and specificity for the identification of rheumatoid arthritis-related cortical hand bone loss

Digital X-ray radiogrammetry (DXR) is a computer-assisted diagnosis technique for quantifying cortical hand bone mineral density (BMD) as well as the metacarpal index (MCI) in the metacarpal bones from radiographs. The objective was to compare DXR-BMD and DXR-MCI between healthy individuals and patients with rheumatoid arthritis (RA) and verify the sensitivity and specificity of this technique for the identification of cortical hand bone loss as an additional diagnostic approach in RA. 618 patients were enrolled and divided into two groups: those with RA (n = 309) and a healthy control group (n = 309) as a reference database. DXR-BMD and the DXR-MCI were measured by DXR using hand radiographs. The severity of RA was evaluated by the modified Larsen score. Mean values for DXR-BMD and DXR-MCI in RA patients were significantly lower compared to healthy subjects (-20.7 and -21.1 %, respectively). Depending on the severity of RA-related joint damage, DXR-BMD revealed a significant reduction of -28.1 % and DXR-MCI -28.2 %, comparing score 1 and score 5 of the modified Larsen score. Both DXR-BMD and DXR-MCI had a high sensitivity (DXR-BMD 91 %, DXR-MCI 87 %) and a moderate specificity (DXR-BMD 47 %, DXR-MCI 49 %) to identify RA-related cortical hand bone loss. The DXR technique seems to be able to quantify RA-related periarticular bone loss as a characteristic feature in the course of RA. Consequently, periarticular osteoporosis seems to function as a reliable diagnostic approach comparable to erosions and joint space narrowing in the diagnosis of RA and as a surrogate marker for the progression of bone loss in RA.

Isolated tuberculosis of metacarpal bone in a 3 year-old child

Primary tuberculosis osteomyelitis of metacarpal bone is rare. The majority of cases occur in children and young adults and there is difficulty in diagnosis mainly in young children. We report a new case in children aged of 3 years, presenting a swelling on the dorsal side of her right hand since 8 months. X-ray showed an expansile, cystic and lytic lesion involving the little finger metacarpal. Tuberculosis was confirmed on histological examination. No lesions in lung parenchyma or lymphadenopathy were associated. Patient was successfully managed by anti-tubercular drugs.

Contrast-enhanced CT facilitates rapid, non-destructive assessment of cartilage and bone properties of the human metacarpal

OBJECTIVE

The aim of this work is to establish the human metacarpal as a new whole joint surface early-stage osteoarthritis (OA) model that enables comparisons of articular cartilage and subchondral bone through high resolution contrast-enhanced CT (CECT) imaging, mechanical testing, and biochemical analysis.

DESIGN

The fourth metacarpal was obtained from 12 human cadaveric donors and baseline μCT imaging was followed by indentation testing. The samples were then immersed in anionic (Ioxaglate) and cationic (CA4+) iodinated contrast agent solutions followed by CECT. Cartilage GAG content and distribution was measured using the 1,9 dimethylmethylene blue (DMMB) assay and Safranin-O histology staining. Linear regression was performed to compare cartilage and subchondral bone properties.

RESULTS

Strong and significant positive correlations were observed between CA4+ CECT attenuation and both GAG content (R(2) = 0.86) and equilibrium modulus (R(2) = 0.84), while correlations using Ioxaglate were insignificant (R(2) ≤ 0.24, P > 0.05). Subchondral bone plate (SBP) thickness negatively and significantly correlated with SBP mineral density (R(2) = 0.49). Cartilage GAG content significantly correlated with several trabecular bone properties, including positive correlations with bone volume fraction (%BV/TV, R(2) = 0.67), trabecular number (Tb.N, R(2) = 0.60), and trabecular thickness (R(2) = 0.42), and negative relationships with structural model index (SMI, R(2) = 0.78) and trabecular spacing (Tb.Sp, R(2) = 0.56). Similarly, equilibrium modulus correlated positively with %BV/TV (R(2) = 0.50), Tb.N (R(2) = 0.59) and negatively with Tb.Sp (R(2) = 0.55) and SMI (R(2) = 0.60).

CONCLUSION

This study establishes the human metacarpal as a new early-stage OA model suitable for rapid, high resolution CECT imaging, mechanical testing, and biochemical analysis of the cartilage and subchondral bone, and for examining their inter-relationships.

[An exceptional association of tuberculosis: clavicular and metacarpal]

We report an exceptional association of metacarpal and clavicular tuberculosis in a two-year-old child with SAFA2 sickle cell disease. We emphasize the role of imaging (X-ray and CT scan) in this work. The definitive diagnosis is confirmed by the pathological examination of biopsy samples. This location should be known in endemic tuberculosis areas.

The association between metacarpal ratio, radiographic hand and knee osteoarthritis and its progression after meniscectomy

OBJECTIVE

To examine whether the ratio of the second and fourth metacarpal bone length (MC2:MC4) in subjects with prior meniscectomy of the knee is associated with radiographic hand and knee osteoarthritis (OA) and its progression.

DESIGN

We assessed 219 subjects (175 men and 44 women) twice with a follow-up time ranging from 4 to 10 years. Participants had all undergone prior meniscectomy. The subjects were of mean (SD) 53 (11) years of age at the first radiographic examination. One observer measured the metacarpal lengths of both hands. We used the average MC2:MC4 from left and right hand divided into tertiles as the exposure variable, using the highest tertile, i.e., "female" pattern as reference category. Radiographic OA of both hands and knees and its progression were evaluated on subject level as our outcomes. We used logistic regression to evaluate the possible association of MC2:MC4 with hand and knee OA and its progression with adjustment for age, sex, body mass index, and follow-up time.

RESULTS

We found no statistically significant association between the lower MC2:MC4 tertile "male" pattern and prevalent hand OA (odds ratio [OR] 0.70; 95% confidence interval [CI] 0.24-1.99) and prevalent knee OA (OR 1.08; 95% CI 0.56-2.07). Neither did we find any corresponding significant association for the progression of hand OA (OR 0.89; 95% CI 0.34-2.32), nor knee OA (OR 0.69; 95% CI 0.33-1.46).

CONCLUSIONS

We did not detect any association between MC2:MC4 and radiographic hand and knee OA and its progression in subjects with prior meniscectomy.

A rare case of massive carpal osteoblastoma requiring complex reconstructive surgery

An osteoblastoma is a rare, commonly benign, osteoid-producing neoplasm of the bone with an incidence of 2% of all primary bone tumours. We present a case of a 54-year-old patient with persisting carpal pain and massive swelling of the hand for a period of 4 years. Incision biopsies revealed the histopathological finding of a carpal osteoblastoma. After complete tumour excision, including the carpal and, in parts, metacarpal bones, reconstructive surgery was performed with a free osteocutaneous iliac crest flap to obtain a natural hand contour and the best possible hand function. Follow-up revealed improvement of the hand function in terms of flexion, extension and strength without discomfort or further pain. Thus, ongoing carpal pain should lead to an intensive search with further diagnostic measures such as magnetic resonance imaging (MRI) scan as well as biopsies, if necessary, to obtain the correct diagnosis.

Operative treatment of Bennett's fracture

We present 89 patients (average age 33 years) with Bennett's fracture (two part fracture to the first metacarpal base). All patients were treated surgically with open reduction internal fixation: 26 patients with K-wires, 19 with titanium mini T-plate, and 44 with titanium osteosynthetic screws (Herbert, AO, TwinFix). The surgical approach we used is a minimal incision of 2-3 cm modification of the radiopalmar curving incision. The Bennett fracture healed and full recovery of function was found between 4-8 weeks. There was no evidence of operative complications, instability of the trapeziometacarpal joint or degenerative changes postoperatively. K-wires were removed in 26 patients after 5-7 weeks, while all other osteosynthetic materials were not removed. We believe that it is important to choose osteosynthetic material according to the type of Bennett fracture to be treated, surgical treatment at the earliest possible time, even if the fracture dislocation is 1 mm. Physical rehabilitation is also important to start as soon as possible.

Candida osteomyelitis in a gelding

A 2-year-old gelding was referred for evaluation of severe right forelimb lameness. The horse was grade 4/5 lame on the right forelimb. Clinical, laboratory, and radiographic findings were consistent with septic arthritis and osteomyelitis. Due to poor prognosis the owner elected euthanasia. Histopathology confirmed chronic arthritis and osteomyelitis with intralesional yeast (Candida species).

Small metacarpal bones of low quality in obese children

OBJECTIVE

It is still not known whether fat mass excess could exert a positive effect on bone. The aim of our study was to evaluate bone strength and quality in a group of overweight and obese children and adolescents by assessing bone geometry at metacarpal bones and ultrasound at phalangeal level.

DESIGN AND PATIENTS

This is a cross sectional observational study performed in 123 subjects, aged 11.2 ± 2.9 years.

MEASUREMENTS

Digitalized X-rays were evaluated at the level of the 2nd metacarpal bone for the determination of the outer (D) and inner (d) diameter, cortical area (CA), medullary endocortical area (EA), metacarpal index (MI) and bone strength (Bending Breaking Resistance Index; BBRI). A total of 98 subjects underwent amplitude dependent speed of sound (Ad-SOS) and bone transmission time (BTT) assessment by phalangeal ultrasonography.

RESULTS

SDs for each measured parameter were as follows: Males: D = -0.71 ± 0.95, d = -0·29 ± 0.86, CA = -0.69 ± 0.69, EA = -0.32 ± 0.79, Ad-SOS = -1.14 ± 0.91, BTT = -1.17 ± 1.11 and BBRI (417 ± 151 vs 495 ± 174 mm(3) ) were all significantly lower than in controls (P < 0.05). Females: D = -1.03 ± 1.06, d = -0.38 ± 0.92, CA = -0.91 ± 0.72, EA = -0.46 ± 0.79, Ad-SOS = -1.08 ± 1.11, BTT = -0.97 ± 1.07 and BBRI (342 ± 117 vs 649 ± 318 mm(3) ) were all significantly lower than in controls (P < 0.05).

CONCLUSIONS

Obese children show an unfavourable bone geometry and a bone of low quality and reduced strength compared to controls at a nonweight bearing skeletal site. This finding seems to support a detrimental effect of fat mass on bone and explain the frequent occurrence of wrist fractures in this group of children.

Assessment of a bone biopsy technique for measuring tiludronate in horses: a preliminary study

This study assessed the feasibility of measuring tiludronate in horses using a minimally invasive bone biopsy technique. Eight horses were treated with intravenous (IV) tiludronate [1 mg/kg bodyweight (BW)], either once (n = 4) or twice, 28 d apart (n = 4). The horses that were treated once were euthanized on days 1, 43, 57, or 92 and those that were treated twice, were euthanized on days 112, 154, 194, or 364. Bone samples were taken bilaterally from each horse at 4 sites: the third metacarpal bone (MCIII), the 13th rib (R13), the tuber coxae (TC), and the cuboid bone (CB). Test samples were taken with a 5-mm diameter dental drill, while larger reference samples were taken with an osteotome. The concentrations of tiludronate were measured by high performance liquid chromatography (HPLC) with ultraviolet (UV) detection. The TC was the easiest site to sample, and no technical difficulties were encountered for extraction and measurement. Drill sampling at the MCIII was difficult. Moreover, both the extraction and measurement caused technical problems and results were unreliable in most cases (93%). Drill samples obtained from the R13 were very small and access to the CB required considerable dissection, which would not be feasible in vivo. Forty-six percent and 36% of the tiludronate measurements performed on the R13 and CB samples, respectively, were unreliable. The ratio of tiludronate concentrations ranged from 73% to 185% (median: 118%) in the TC, 65% to 208% (median: 81%) in the R13, and 26% to 110% (median: 57%) in the CB. In all but 1 horse, the highest concentrations of tiludronate were found in the TC. It was concluded that bone biopsies performed at the TC were adequate for measuring tiludronate in horses and should be considered in future for repeated measurements over time in living animals.

Giant cell tumour of first metacarpal bone

Giant cell tumour (GCT) or osteoclastoma is a benign locally aggressive tumour with a tendency for local recurrence. 85-90% of cases occur in long bones; the sites most commonly affected being lower end of femur, upper end of tibia, lower end of radius and proximal humerus in descending order of frequency. Only 2% of GCT occurs in hand. GCT of bone accounts for 5% of all primary bone tumour. 80% of patients are above the age of 18 years, and it occurs commonly in adults between ages of 20 and 40 years. The authors report a case of GCT of first metacarpal which is very rare site for such tumour and only few cases reported in literature so far.

Third metacarpal condylar fatigue fractures in equine athletes occur within previously modelled subchondral bone

Bone modelling and remodelling reduce the risk of fatigue fractures; the former by adapting bone to its loading circumstances, the latter by replacing fatigued bone. Remodelling transiently increases porosity because of the normal delay in onset of the formation phase of the remodelling sequence. Protracted intense loading suppresses remodelling leaving modelling as the only means of maintaining bone strength. We therefore hypothesized that race horses with fatigue fractures of the distal third metacarpal bone (MC3) will have reduced porosity associated with suppressed remodelling while continued adaptive modelling will result in higher volume fraction (BV/TV) at this site. Using high resolution peripheral quantitative computed tomography (HR-pQCT), we measured the distal aspect of the MC3 obtained at postmortem from 13 thoroughbred race horses with condylar fractures of the MC3 (cases), 8 horses without fractures (training controls), 14 horses with a fracture at another site (fractured controls) and 9 horses resting from training (resting controls). Porosity of the subchondral bone of MC3 was lower in cases than resting controls (12±1.4% vs. 18±1.6%, P=0.017) although areas of focal porosity were observed adjacent to fractures in 6/13 horses. BV/TV of the distal metacarpal epiphysis tended to be higher in horses with condylar fractures (0.79±0.015) than training controls (0.74±0.019, P=0.070), but also higher in controls with a fracture elsewhere (0.79±0.014) than the training controls (0.74±0.019, P=0.040). BV/TV was higher in horses over three years of age than those aged two or three years (0.79±0.01 vs. 0.74±0.01, P=0.016). All metacarpal condylar fractures occurred within focal areas of high BV/TV. We infer that intense training in equine athletes suppresses remodelling of third metacarpal subchondral bone limiting damage repair while modelling increases regional bone volume in an attempt to minimise local stresses but may fail to offset bone fragility.

[Tumor-segmental resection of hand-foot-giant cell tumor of bone and autologous iliac bone graft reconstruction]

OBJECTIVE

To evaluate the effectiveness of tumor-segmental resection and autologous iliac bone graft reconstruction combined with internal fixation in treating hand-foot-giant cell tumor of bone.

METHODS

Between August 1997 and April 2008, 8 cases of hand-foot-giant cell tumor of bone were treated, including 3 males and 5 females with an average age of 28.5 years (range, 16-42 years). The locations were metacarpal bones in 3 cases, metatarsal bones in 4 cases, and phalanges of toes in 1 case. According to Campanacci's gradation of X-ray films, there were 1 case of grade I and 7 cases of grade II; according to pathological examination before operation, there were 3 cases of grade I to II, 4 cases of grade II, and 1 case of grade II to III; and according to TNM staging, there were 1 case of TisN0M0, 4 cases of T1N0M0, and 3 cases of T2N0M0. There were 2 cases of recurrence, the time from the first operation to recurrence were 11 and 14 months, respectively. The tumor size was 1.8 cm x 1.0 cm to 6.0 cm x 2.0 cm, the cortical bone became thinner, and the boundary between tumor and periosteum was clear. All patients underwent tumor-segmental resection combined with autologous iliac bone graft reconstruction, and miniplate internal fixation by lumbar anesthesia or trachea cannula anesthesia.

RESULTS

All incision healed by first intention. Eight patients were followed up 10 to 84 months with an average of 46 months. Radiographs showed that fracture union was achieved at 3 to 9 months (mean, 5 months). No significant rotation, angular, and shortening deformity occurred in iliac bone graft. The function of iliac bone donor site recovered excellently. The pathological examination showed giant cell tumor of bone in all cases, including 2 case of grade I-II, 5 cases of grade II, and 1 case of grade II-III. The hand or foot function recovered excellently. No tumor recurrence or lung metastasis occurred during follow-up.

CONCLUSION

Tumor-segmental resection combined with autologous iliac bone graft reconstruction plus internal fixation has excellent effectiveness for hand-foot-giant cell tumor of bone.

Gene expression markers of tendon fibroblasts in normal and diseased tissue compared to monolayer and three dimensional culture systems

BACKGROUND

There is a paucity of data regarding molecular markers that identify the phenotype of the tendon cell. This study aims to quantify gene expression markers that distinguish between tendon fibroblasts and other mesenchymal cells which may be used to investigate tenogenesis.

METHODS

Expression levels for 12 genes representative of musculoskeletal tissues, including the proposed tendon progenitor marker scleraxis, relative to validated reference genes, were evaluated in matched samples of equine tendon (harvested from the superficial digital flexor tendon), cartilage and bone using quantitative PCR (qPCR). Expression levels of genes associated with tendon phenotype were then evaluated in healthy, including developmental, and diseased equine tendon tissue and in tendon fibroblasts maintained in both monolayer culture and in three dimensional (3D) collagen gels.

RESULTS

Significantly increased expression of scleraxis was found in tendon compared with bone (P = 0.002) but not compared to cartilage. High levels of COL1A2 and scleraxis and low levels of tenascin-C were found to be most representative of adult tensional tendon phenotype. While, relative expression of scleraxis in developing mid-gestational tendon or in acute or chronically diseased tendon did not differ significantly from normal adult tendon, tenascin-C message was significantly upregulated in acutely injured equine tendon (P = 0.001). Relative scleraxis gene expression levels in tendon cell monolayer and 3D cultures were significantly lower than in normal adult tendon (P = 0.002, P = 0.02 respectively).

CONCLUSION

The findings of this study indicate that high expression of both COL1A2 and scleraxis, and low expression of tenascin-C is representative of a tensional tendon phenotype. The in vitro culture methods used in these experiments however, may not recapitulate the phenotype of normal tensional tendon fibroblasts in tissues as evidenced by gene expression.

Clinics in diagnostic imaging (124). Multiple enchondromatosis in Ollier disease

A three-year-old girl presented with slow-growing swellings at the left foot and upper right humerus. Radiographs show multiple enchondromas in both feet, proximal humeri and scapulae, as well as at multiple sites in the hands, distal forearm bones and pelvis, in keeping with multiple enchondromatosis in Ollier disease. The clinical presentation and imaging features of enchondromas and the different types of enchondromatosis are discussed.

Hand bone loss as an outcome measure in established rheumatoid arthritis: 2-year observational study comparing cortical and total bone loss

The aim of this 2-year longitudinal observational study was to explore hand bone loss as a disease outcome measure in established rheumatoid arthritis (RA). A cohort of 215 patients with RA (170 women and 45 men, aged 20-70 years) were recruited from the Oslo RA registry and studied for changes in hand bone mass during a 2-year follow-up. Digital X-ray radiogrammetry (DXR) was used to measure cortical hand bone mineral density (BMD) and metacarpal cortical index, whereas dual-energy X-ray absorptiometry (DXA) was used to assess whole hand BMD, which measures total cortical and trabecular bone. DXA-BMD total hip and spine and informative data for disease and therapy were also collected. Hand bone loss could be revealed over a 2-year follow-up measured by DXR-BMD (-0.90%, P < 0.01), but not by DXA-BMD (0.00%, P = 0.87). DXA-BMD hand bone loss was only observed in patients with disease duration < or = 3 years and not in patients with longer disease duration (-0.96% versus 0.24%, P < 0.01), whereas loss of DXR-BMD was independent of disease duration. Disease activity (measured by the disease activity score including 28 joints) independently predicted loss of DXR-BMD but not changes in the DXA-BMD hand in the multivariate analysis. The change in DXR metacarpal cortical index was highly correlated to DXR-BMD (r = 0.94, P < 0.001). These data suggest that DXR-BMD may be a more appropriate technique to identify RA-related bone involvement in hands compared with DXA-BMD measurement, but further studies are needed to explore this hypothesis.

Sodium zeolite a supplementation and its impact on the skeleton of dairy calves

Twenty calves were placed on study at 3 days of age and were placed according to birth order into one of two groups: SS, which received 0.05% BW sodium zeolite A (SZA) added to their milk replacer, and CO, which received only milk replacer. Blood samples were taken on days 0, 30, and 60 for osteocalcin (OC) and deoxypyridinoline (DPD) analysis. On day 60, the calves were euthanized, and synovial fluid, articular cartilage, and both fused metacarpals were collected for bone quality analyses such as architecture and mechanical properties, mineral composition, and glycosaminoglycan concentration. There were no differences in OC concentrations because of treatment (p = 0.12), and CO calves had lower DPD concentrations than SS calves (p = 0.01), but the OC-to-DPD ratio was not different between treatments (p = 0.98). No differences in bone architecture or mechanical properties were detected. SZA supplementation increased cortical bone (p = 0.0002) and articular cartilage (p = 0.05) aluminum content. Glycosaminoglycan concentrations were not different in synovial fluid or cartilage. Supplementation of SZA appeared to alter the rate of bone turnover without altering bone strength. Aluminum concentrations in the bone and cartilage increased, which may be a concern, although the long-term consequences of such remain to be determined.

Jaccoud arthropathy in systemic lupus erythematosus: analysis of clinical characteristics and review of the literature

Jaccoud arthropathy (JA) was initially described in patients with rheumatic fever and later in several other rheumatologic conditions, particularly systemic lupus erythematosus (SLE). In patients with the latter disorder, a prevalence of about 5% has been observed. We conducted the current study to describe a series of patients with SLE with JA, followed at the Hospital Santa Izabel, Salvador, Brazil, during the year 2006. We reviewed the literature on JA, with emphasis on the histologic, clinical, radiologic, and therapeutic aspects of the condition. Twenty-one patients with JA were identified, corresponding to a prevalence of 3.47% in the population of 606 patients with the diagnosis of SLE attended in our service. Twenty patients were women, and the mean age was 40.2 +/- 8.8 years (range, 24-55 yr). The most frequently found joint deformities were swan neck and thumb subluxation, both identified in 14 patients. Ulnar deviation was seen in 8, boutonniere deformity in 3, and hallux valgus in 2 patients. We found no difference in the clinical or laboratory features in SLE patients with or without JA. The patients with JA presented a trend toward a lower quality of life compared with the patients with SLE without JA, but without statistical significance.

Metastasis of squamous-cell carcinoma of the lung to the first web space of the hand

While primary squamous-cell carcinoma of the hand is common, metastasis of a squamous-cell carcinoma to the hand is very rare. It has been reported to arise from carcinoma of the lung and oesophagus and, rarely, from other tumours. We describe a patient with metastatic squamous-cell carcinoma occurring in the first web space of the hand from primary lung cancer, which remained undetected for 30 months after treatment of the metastasis.

Kystes anévrismaux des phalanges et des métacarpiens. À propos de six cas et revue de la littérature

Aneurysmal bone cysts arising from tubular bones of the hand occur very rarely and require particular diagnostic and therapeutic management techniques. The authors report the diagnostic and surgical management of a monocentric case series of six aneurysmal bone cysts involving the phalangeal and metacarpal bones. In addition to hightlighting the use of diagnostic MRI and biopsy prior to surgical intervention, the authors describe the favourable outcome of curetage with and without the use of bone graft. An aggressive treatment approach such as cryotherapy or resection with reconstruction should only be used in cases when the articular surface is involved, when full bone invasion of the phalanx or metacarpal has occurred, or in case of more than one recurrence.

Novel karyotypes in giant cell-rich lesions of bone

Giant cell-rich lesions of bone, including giant cell tumor of bone, giant cell reparative granuloma (GCRG), and aneurysmal bone cyst (ABC), may have overlapping clinical, radiologic, and histopathologic features. In fact, GCRG and solid ABC are currently differentiated solely based on skeletal location. Prior cytogenetic studies have reported that telomeric associations are present in the majority of giant cell tumors of bone, whereas translocations involving 16q22 and/or 17p13 are characteristic of ABCs. There is only one previously published karyotype of a GCRG, which revealed a reciprocal translocation, t(X;4)(q22;q31.3). We report 3 cases of giant cell-rich bone lesions with novel karyotypes: one lesion located in the first metacarpal, a typical location for GCRG, was histologically consistent with a giant cell tumor and showed the following karyotype [46,XX,inv(2)(p13q21),t(inv2;11)(q21;q13)]; the second lesion, also a giant cell tumor of bone, in the sacrum showed the following karyotype [46,XX,r(9)(p24q34)[cp7]/46,idem,?r(16)(p13.3q24)[cp10]/46,XX]. The third lesion, a hard palate mass, had the histopathologic features of a GCRG and a karyotype showing a reciprocal translocation, 46,XY,t(2;10)(q23;q24). These findings suggest that at least a subset of GCRGs may be neoplastic and that these lesions differ cytogenetically from classic giant cell tumors of bone or solid ABC, although the latter entity is otherwise indistinguishable from reparative granuloma. Further cytogenetic characterization of giant cell-rich bone lesions may improve the utility of karyotyping as a tool in their differential diagnosis and may shed light on the pathogenetic relationship between these lesions.

Rheumatoid arthritis bone erosion volumes on CT and MRI: reliability and correlations with erosion scores on CT, MRI and radiography

OBJECTIVES

To investigate intramodality and intermodality agreements of CT and MRI erosion volumes in metacarpophalangeal (MCP) joints in rheumatoid arthritis (RA), and to compare the volumes with erosion scores for CT, MRI and radiography.

METHODS

In total, 17 patients with RA and four healthy controls underwent unilateral CT, MRI and radiography of second to fifth MCP joints in one hand. Erosion volumes (using OSIRIS software) and scores were determined from CT, MRI and radiography (scores only).

RESULTS

CT, MRI and radiography detected 77, 62 and 12 erosions, respectively. On CT, the mean erosion volume was 26 mm(3) (median 10; range 0 to 248) and 30 mm(3) (18; 1 to 163) on MRI. Total erosion volumes (per patient/control) were 97 mm(3) (29; 0 to 485) on CT and 90 mm(3) (46; 0 to 389) on MRI. For volumes, Spearman correlation coefficients were 0.96 to 0.99 (CT vs CT), 0.95 to 0.98 (MRI vs MRI) and 0.64 to 0.89 (CT vs MRI), all p<0.01. MRI erosion volumes correlated with the Outcome Measures in Rheumatology Clinical Trials/Rheumatoid Arthritis Magnetic Resonance Imaging Score (OMERACT RAMRIS) erosion scores (0.91 to 0.99; p<0.01) and the Sharp/van der Heijde erosion score (0.49 to 0.63; p<0.01).

CONCLUSION

Very high intramodality and high intermodality agreements of CT and MRI erosion volumes were found, encouraging further testing in longitudinal studies. A close correlation with CT and MRI erosion volumes supports the OMERACT RAMRIS erosion score as a valid measure of joint destruction in RA.

Alternative surgical treatment for giant-cell reparative granuloma in the metacarpal, using phenol and ethanol adjuvant therapy

Giant-cell reparative granuloma (GCRG) or a solid variant of an aneurysmal bone cyst (ABC) is an uncommon benign reactive lesion with a predilection for the small tubular bones of the hands and feet. Treatment usually involves wide resection or amputation because of unacceptable high recurrence rates after curettage. Adjuvant therapy usually is applied to reduce the recurrence of locally aggressive bone tumors. We report 2 cases of GCRG that were treated successfully with curettage, adjuvant phenol and ethanol, and autogenous bone grafting.

Comparative assessment of bone mass and structure using texture-based and histomorphometric analyses

The purpose of this study was to develop a methodology for quantitatively assessing bone quantity and anisotropy based on texture analysis using Gabor wavelets. The wavelet approach has the capability to simultaneously examine the images at low and high resolutions to gain information on both global and detailed local features of the bone image. The program that implemented the texture analysis gave measures of density (M(Density)) and anisotropy (M(Anisotropy)). It also allowed us to examine the texture energy at four orientations (0 degrees , 45 degrees , 90 degrees , 135 degrees) to gain insight about the details of the anisotropy. Analysis of templates of four simulated patterns, which had same number of dots but with differing orientations, demonstrated how the texture-based analysis differentiated between these templates. The measures of M(Anisotropy) discriminated between the four simulated patterns. The M(Density) measures were similar across all patterns. These outcomes matched the design intent of the simulated patterns. We also compared the trabecular bone images obtained from a previous study, in which the right forelimbs of normal female retired breeder beagle dogs (5-7 years old) were cast for 12 months to induce bone loss, using both histomorphometry and texture analysis. Both histomorphometry and the texture analysis detected significant differences in the trabecular bone of the distal metatarsal between the control and disuse groups. Percent trabecular bone (Tb.Ar/T.Ar) and the textural density parameter (M(Density)) were highly correlated (r=0.962). M(Anisotropy) was decreased (3.9%) after the 12-month disuse protocol, but was not significantly different from normal. However, the texture energy values at all orientations (0 degrees , 45 degrees , 90 degrees and 135 degrees) were significantly decreased in the disuse group. Therefore, texture analysis was able to assess anisotropy, which could not be extracted from histomorphometric parameters. We conclude that texture analysis is an effective tool for assessing 2D bone images that yields information regarding the quantity of bone as well as the orientation of the trabecular structure that can augment our ability to discriminate between normal and pathological bone tissue.

Rhizarthrose juvénile bilatérale dans une laxité constitutionnelle

We report a rare case of major trapezometacarpal instability observed in a 31-year-old woman with congenital hyperlaxity. The patient presented major functional impotency of both thumbs, closure of the first commissure, and absence of effective opposition except between the lateral borders of the long fingers due to severe pain in the trapezometacarpal joint attributed to osteoarthritis. The patient underwent bilateral trapezectomy with ligamentoplasty. The gross examination of the trapezeal specimens revealed major cartilage destruction on the medial portion of the trapezeal joint surface. Three months after surgery, the patient was able to resume occupational and recreational activities. At one year, she was pain free with normal function. No other similar case could be identified in the literature and search for a pathological condition which could have contributed to the altered collagen was negative. It was observed that since stabilization was achieved by ligamentoplasty, recurrence should not be expected in congenital hyperlaxity if the tendons are unaffected.

Congenital proximal radioulnar synostosis associated with bilateral hypoplasia of the scaphoid bone, bilateral os lunatotriquetrum, and anomalies of the carpometacarpal complex

We describe a unique case of bilateral os lunatotriquetrum associated with bilateral hypoplasia of the scaphoid bone. On both sides, the medial carpi were in a single row. The capitate bone occupied the lunate position, whereas the lunatotriquetral bone was displaced ulnarly and tilted. The capitate thus articulated with the radius and metacarpal bones, consistent with carpal collapse. In addition, there was congenital proximal radioulnar synostosis on the left side.

Comparison of Radiography and Computed Tomography to Evaluate Metacarpo/Metatarsophalangeal Joint Pathology of Paired Limbs of Thoroughbred Racehorses with Severe Condylar Fracture

OBJECTIVE

To compare the orthogonal radiographic (OR) and computed tomographic (CT) appearance of paired Thoroughbred racehorse limbs with severe condylar fracture.

STUDY DESIGN

In vitro study.

SAMPLE POPULATION

Cadaveric paired limbs with severe condylar fracture (n=11 horses).

METHODS

Four standard radiographic and multiple transverse CT images were obtained of the fractured and contralateral limbs centering on the metacarpo/metatarsophalangeal (fetlock) joints. Radiographs and CT images were graded by 4 raters, and interobserver agreement was calculated. Imaging evaluations were supplemented by fetlock joint dissection. A consensus description of actual injury and the detection accuracy of OR and CT for that injury was determined. Results- Rater agreement for OR and CT for most pathologic features was good or excellent. OR was similar to CT for the detection of condylar and diaphyseal third metacarpal and metatarsal (MC/MT3) fractures, diaphyseal fractures of the first phalanx (P1), and fracture location on the condyle. CT was superior to OR for detection of MC/MT3 proximal fissures and articular comminution, condylar small cracks and lucencies, and proximal sesamoid fractures. OR was superior to CT for detection of proximal P1 dorsal fractures. Both OR and CT were poor at detecting palmar/planter proximal P1 fractures and coalescing cracks in the subchondral bone of MC/MT3.

CONCLUSIONS

CT is better than OR for detection of pathology in limbs with condylar fractures, but does not detect every pathologic feature.

CLINICAL RELEVANCE

CT provides superior information of pathology in Thoroughbred racehorses with condylar fractures.

Did ice-age bovids spread tuberculosis?

Pathognomonic metacarpal undermining is a skeletal pathology that has been associated with Mycobacterium tuberculosis in bovids. Postcranial artiodactyl, perissodactyl, and carnivore skeletons were examined in major university and museum collections of North America and Europe for evidence of this and other pathology potentially attributable to tuberculosis. Among nonproboscidean mammals from pre-Holocene North America, bone lesions indicative of tuberculosis were restricted to immigrant bovids from Eurasia. No bone lesions compatible with diagnosis of tuberculosis were found in large samples of other pre-Holocene (164 Oligocene, 397 Miocene, and 1,041 Plio-Pleistocene) North American mammals, including 114 antilocaprids. Given the unchanged frequency of bovid tubercular disease during the Pleistocene, it appears that most did not die from the disease but actually reached an accommodation with it (as did the mastodon) (Rothschild and Laub 2006). Thus, they were sufficiently long-lived to assure greater spread of the disease. The relationships of the proboscidean examples need further study, but present evidence suggests a Holarctic spread of tuberculosis during the Pleistocene, with bovids acting as vectors. While the role of other animals in the transmission of tuberculosis could be considered, the unique accommodation achieved by bovids and mastodons makes them the likely "culprits" in its spread.

Can the carpometacarpal joint be injected accurately in the office setting? Implications for therapy

OBJECTIVE

To investigate whether carpometacarpal (CMC) injections can be performed accurately in the office setting in patients with moderate to severe CMC osteoarthritis (OA).

METHODS

Patients were recruited from rheumatology and hand surgical practices as part of an open label trial of hylan G-F 20 for CMC OA. CMC injections were performed without radiologic guidance, using anatomic landmarks to guide needle placement. Once injected, the patient was immediately taken to an adjacent ultrasound suite, and the injected CMC joint examined for evidence of intraarticular material and air microbubbles.

RESULTS

Thirty-two patients were injected. All patients had ultrasound evidence of intraarticular material: 91% also had evidence of microbubbles in the joint.

CONCLUSION

CMC injections can be performed accurately in the office setting, without the need for radiologic guidance, in patients with moderate to severe CMC OA.