Cell engraftment, vascularization, and inflammation after treatment of equine distal limb wounds with endothelial colony forming cells encapsulated within hydrogel microspheres.

BACKGROUND: Endothelial colony forming cells (ECFCs) may be useful therapeutically in conditions with poor blood supply, such as distal limb wounds in the horse. Encapsulation of ECFCs into injectable hydrogel microspheres may ensure cell survival and cell localization to improve neovascularization and healing. Autologous ECFCs were isolated from 6 horses, labeled with quantum nanodots (QD), and a subset were encapsulated in poly(ethylene) glycol fibrinogen microspheres (PEG-Fb MS). Full-thickness dermal wounds were created on each distal limb and injected with empty PEG-Fb MS, serum, ECFCs, or ECFCs encapsulated into PEG- Fb MS (ECFC/MS). Analysis included wound surface area (WSA), granulation tissue scoring (GS), thermography, collagen density staining, and immunohistochemical staining for endothelial and inflammatory cells. The purpose of this study was to track cell location and evaluate wound vascularization and inflammatory response after injection of ECFC/MS or naked ECFCs in equine distal limb wounds. RESULTS: ECFCs were found near and within newly formed blood vessels up to 3 weeks after injection. ECFC and ECFC/MS groups had the greatest blood vessel quantity at week 1 in the wound periphery. Wounds treated with ECFCs and ECFC/MS had the lowest density of neutrophils and macrophages at week 4. There were no significant effects of ECFC or ECFC/MS treatment on other measured parameters. CONCLUSIONS: Injection of microsphere encapsulated ECFCs was practical for clinical use and well-tolerated. The positive ECFC treatment effects on blood vessel density and wound inflammation warrant further investigation.

[Analysis on Injury Manners of 31 Cases of Bennett Fracture and Rolando Fracture].

OBJECTIVES: To study the injury manners of Bennett fracture and Rolando fracture and explore its identification principle of the first metacarpal base fractures. METHODS: Totally 31 cases of Bennett fracture and Rolando fracture were collected. The injury manners of cases of 19 Bennett fractures and 12 Rolando fracture were classified, and various injury manners were analysed statistically. RESULTS: The injury manners of the cases of 19 Bennett fracture and 12 Rolando fracture were divided into three types, including the first metacarpus hit hard objects during a punching, the first metacarpus hit hard objects when making fists and fell, or the first metacarpus was punched by hard objects when making fists. CONCLUSIONS: The injury mechanism of Bennett fracture and Rolando fracture is formed by a force on the first metacarpus when making fists, which transmits to the basilar part along the vertical axis of metacarpus. The inference of injury manners should be focused on the confirmation of entrusted matters.

Open reduction and internal fixation for intraarticular fracture of metacarpal head.

Intraarticular fracture of the metacarpophalangeal (MP) joint presents complex problems related to the sophisticated functional aspects of the hand. Injury to the metacarpal head may have a severe effect on hand function but few studies have investigated the management of this condition. In this study, we applied open reduction and internal fixation for the displaced fracture of the metacarpal head and report the clinical and radiographic outcomes of our experience. Thirteen patients (12 men, 1 woman; mean age 21 years) were included in this study, and medical records and radiographs were reviewed retrospectively. The average follow-up period was 12.5 months. Range of motion (ROM) and Disabilities of the Arm, Shoulder, and Hand (DASH) scores were analyzed, and functional results and serial radiographs were investigated for the maintenance of articular congruity and fracture union. The injured fingers were 5 long, 4 small, 2 ring, and 2 index. Five cases were fixed with K­wires, 5 cases with headless screws, and 3 cases with screw and K­wire. The average range of injured MP joint motion was 89°, total active range of motion (TAM) was 265°, and the average DASH score was 3.8 at the last follow-up. All patients showed fracture union on the radiographs and no patient showed significant articular surface incongruence or degenerative change. Open reduction and internal fixation of the metacarpal head fracture had favorable outcomes in our study. The authors suggest accurate reduction and stable fixation for better functional results in metacarpal head fractures.

Physeal Fractures in Foals.

Physeal fractures are common musculoskeletal injuries in foals and should be included as a differential diagnosis for the lame or nonweightbearing foal. Careful evaluation of the patient, including precise radiographic assessment, is paramount in determining the options for treatment. Prognosis mostly depends on the patient's age, weight, and fracture location and configuration.

Clenched fist injury complicated by septic arthritis and osteomyelitis treated with negative pressure wound therapy: One case report.

We reported a 30 years old man who suffered a bite wound of the right hand in a fight. Two days after the injury, he was admitted in emergency because of stab wound above the head of the third metacarpal bone. He presented the swelling, redness, pain and fever. Primary revision confirmed only partial lesion of the extensor apparatus. During the following days, we recorded a deterioration of local findings and magnetic resonance imaging revealed osteomyelitis and septic arthritis of the thirdmetacarpophalangeal joint. The wound was then revised several times using negative pressure wound therapy in combination with intravenous antibiotics. After resolution of clinical and laboratory findings, the wound was finally closed by delayed primary suture. Clenched fist injury is a medical emergency that requires immediate surgical revision. We treated clenched fist injury with the development of septic arthritis and osteomyelitis with negative pressure wound therapy and obtained good outcomes.

Identification of cartilage injury using quantitative multiphoton microscopy.

OBJECTIVE: Cartilage injury can lead to post-traumatic osteoarthritis (PTOA). Immediate post-trauma cellular and structural changes are not widely understood. Furthermore, current cellular-resolution cartilage imaging techniques require sectioning of cartilage and/or use of dyes not suitable for patient imaging. In this study, we used multiphoton microscopy (MPM) data with FDA-approved sodium fluorescein to identify and evaluate the pattern of chondrocyte death after traumatic injury. METHOD: Mature equine distal metacarpal or metatarsal osteochondral blocks (OCBs) were injured by 30 MPa compressive loading delivered over 1 s. Injured and control sites were imaged unfixed and in situ 1 h post-injury with sodium fluorescein using rasterized z-scanning. MPM data was quantified in MATLAB, reconstructed in 3-D, and projected in 2-D to determine the damage pattern. RESULTS: MPM images (600 per sample) were reconstructed and analyzed for cell death. The overall distribution of cell death appeared to cluster into circular (n = 7) or elliptical (n = 4) patterns (p = 0.006). Dead cells were prevalent near cracks in the matrix, with only 26.3% (SE = 5.0%, p < 0.0001) of chondrocytes near cracks being viable. CONCLUSION: This study demonstrates the first application of MPM for evaluating cellular-scale cartilage injury in situ in live tissue, with clinical potential for detecting early cartilage damage. With this technique, we were able to uniquely observe two death patterns resulting from the same compressive loading, which may be related to local variability in matrix structure. These results also demonstrate proof-of-concept MPM diagnostic use in detecting subtle and early cartilage damage not detectable in any other way.

Interobserver variability in the treatment of little finger metacarpal neck fractures.

PURPOSE: To address the null hypothesis that surgeons shown radiographs of little finger metacarpal neck fractures with measured fracture angulation would recommend surgery as often as surgeons shown unmarked radiographs. METHODS: Members of the Science of Variation Group, an international collaboration of fully trained orthopedic and trauma surgeons, were asked to review 20 little finger metacarpal neck fracture cases, which included a vignette and 3 high-quality radiographs. Members were then randomized to review radiographs with or without measured fracture angulation on the lateral view and select operative or nonoperative management. RESULTS: Surgeons shown radiographs with measured angulation were more likely to recommend surgery, and there was less variability among these surgeons, particularly for fractures with less angular deformity. CONCLUSIONS: Measured fracture angulation has a small but significant influence on treatment recommendations for little finger metacarpal neck fractures. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic III.

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.

Reconstruction of hand injuries with multiple metacarpal defects using free fibular osteoseptocutaneous flap.

Hand injuries with multiple metacarpal involvements often include midpalmar muscle, extensor tendon, and skin defects. Reconstruction method is decided according to the type and amount of structures to be restored. Bone reconstruction and resurfacing of the skin is regarded as priority, and restoration of tendon function and joint mobility can be left for further procedures. An ideal flap for such defects should provide bone for multiple metacarpal defects and a large enough skin paddle. Such flaps are few, and one of the most suitable of them all is the free fibular osteoseptocutaneous flap (free FOSCF). In this report, our experience with the use of free FOSCF for reconstruction of the mutilating hand injury in five patients with extensive skin integument and metacarpal involvement has been presented. Total lengths of fibular flaps were averagely 11 cm in length and were divided into averagely 2.4 segments. Average dimensions of the skin paddles were 7.75 × 8.75 cm. Although the nature of the devastating traumas limited the ultimate functional recovery; wound closure, stability, and various degrees of mobility were restored in all patients. In our experience, reconstruction with free FOSCF proved to be an effective tool in mutilating hand injuries with metacarpal involvement.

Morphological analysis of third metacarpus cartilage and subchondral bone in Thoroughbred racehorses: An ex vivo study.

Racehorses are exposed to repetitive overload during training and competition, causing joint hyperextension, tissue fatigue, and ultimately skeletal failure. Some degree of bone changes, such as sclerosis, are expected in equine athletes, as adaptation to the biomechanical rigors of training and racing. Understanding the imaging characteristics of the equine joint surface and subchondral bone would allow earlier detection of injuries or adaptation, improving prognosis and training programs. This study sought to describe the joint surface structural patterns and the periarticular structures of the third metacarpal bone (MC3). Both forelimbs of eight horses engaged in daily training programs, aged 3-5 years, which were euthanized for reasons unrelated to the metacarpophalangeal (MCP) joints, were collected. Specimens were evaluated through macroscopic inspection, radiography, ultrasonography, and microscopic examinations, such as optical microscopy and microtomography. Analysis of the microtomography images showed that 50% of the samples had higher trabecular thickness in the lateral condyle. Comparison of each imaging examination revealed that ultrasound images were most closely related to the histological examination (p = .29) in terms of sensitivity, while macroscopic and radiographic examinations differed most between evaluators. Finally, the irregularities and modifications observed in the articular cartilage surface and subchondral bone were normal adaptations of the anatomical structures of trained racehorses, which should be considered during clinical examination.

A dislocation of the carpal-metacarpal joints of the index, middle and ring finger.

A dislocation of the carpal-metacarpal joints of the index, middle and ring finger is reported. This dislocation is not very common and can easily be missed without the right diagnostics. The lesion was treated by reduction and immobilization for four weeks. Two months after the trauma, the patient had regained full function of his hand.

Effect of bandaging on second intention healing of wounds of the distal limb in horses.

OBJECTIVE: To evaluate the effect of a non-occlusive dressing incorporated in a 3-layer bandage on second intention healing of wounds of the distal portion of the limb. STUDY DESIGN: Untreated wounds in 33 adult horses used in four studies using the same wound-healing model conducted over 5 years. METHODS: Standardised, full-thickness wounds were made in the skin overlying the dorsomedial aspect of the mid-metacarpus; 17 horses were bandaged with a non-occlusive dressing covered by gauze-coated cotton wool that was compressed with adhesive tape; 16 horses were left unbandaged. Wounds were photographed weekly for 9 weeks and the images were analysed electronically. RESULTS: There were significant effects associated with bandage (P < 0.0001), week (P < 0.001), and bandage by week interaction (P < 0.0001). There was no difference in wound area at the first time-point after wound creation (P = 0.38). After week 1, there was a difference between bandaged and unbandaged wounds in wound area at each measurement until the end of the study. Bandaged wounds showed greater and more prolonged retraction. Unbandaged wounds retracted for 2 weeks before beginning to contract, whereas bandaged wounds continued to retract for 3 weeks. In bandaged wounds excess granulation tissue required regular trimming, but not in unbandaged wounds. There was no difference between groups in the total days to healing or the overall rate of healing. CONCLUSIONS: These results should be treated with caution until validated with contemporaneous, controlled studies. Covering a wound with a non-occlusive dressing in a 3-layer bandage led to greater wound retraction, modulated the rate of wound contraction and promoted excessive granulation tissue. If excessive granulation tissue is excised regularly, bandaging has no effect on total time to healing.

[Acute traumatic dislocation of the trapeziometacarpal joint treated by percutaneous pinning. Review of six cases]. / La luxation trapézométacarpienne post-traumatique récente traitée par brochage selon Wiggins. A propos de six cas.

The authors report a series of six cases of acute traumatic dislocation of the trapeziometacarpal joint of the thumb. Displacement was always dorso-radial. There were associated osseous lesions in one patient: avulsion of the palmar tubercle of the base of the first metacarpal with a fracture of the trapezoid. All the patients were treated immediately by percutaneous pinning according to the technique of Wiggins. The late results, evaluated at an average of 19 months postinjury (range: 8-29 months), were considered to be satisfactory in the majority of the patients. Treatment by percutaneous pinning remains a less sophisticated alternative that in our experience yields consistently good results, provided there is no preexisting degenerative articular lesion.

Hypothenar hammer syndrome: case reports and brief review.

Patients with hand and finger pain regularly present to primary care practices. Although a well-known clinical entity to specialists, hypothenar hammer syndrome is an uncommon vascular overuse syndrome that may not be familiar to primary care practices. It is caused by trauma to the palmar portion of the ulnar artery, usually as a result of occupational or sports activities which involve repetitively striking objects with the heel of the hand. In this report we describe two representative cases as well as discuss clinical features, pathogenesis, diagnosis, imaging and management.

Epoxy putty external skeletal fixation for fractures of the four main metacarpal and metatarsal bones in cats and dogs.

The objective of this retrospective study was to report the clinical use, advantages, disadvantages, complications and outcome of an epoxy putty external skeletal fixator (EPESF) used for the repair of fractures of all four main metatarsal or metacarpal bones in a single limb in 11 dogs and 11 cats. The aim of this technique was to achieve satisfactory alignment of the proximal and distal joints and the digits, rather than anatomical reconstruction of the metacarpal/metatarsal bones themselves. All of the cases achieved fracture union and they all recovered fully without any residual lameness.

[Treatment of metacarpal fractures with open reduction and low-profile plate and screw fixation]. / Metakarp kiriklarinin açik redüksiyon ve düsük profilli plak vida sistemi ile tedavisi.

OBJECTIVES: We evaluated functional results and effectiveness of open reduction and low-profile plate fixation for the treatment of low-severity metacarpal fractures. METHODS: We retrospectively reviewed 50 metacarpal fractures of 43 patients (37 men, 6 women; mean age 31+/-9 years; range 17 to 52 years) who were treated with open reduction and low-profile plate fixation. Fractures of the first metacarpal were excluded. There were 26 oblique, 12 transverse, and 12 comminuted fractures. Three fractures were open. Objective assessment included total active motion (TARM) and grip strength. Subjective assessment was made using the Turkish version of the Quick-DASH scale. Radiographic evaluations were made on anteroposterior/lateral and oblique roentgenograms. Complications were classified as major or minor according to the Page-Stern system. The mean follow-up was 62.2+/-24.8 months (range 12 to 96 months). RESULTS: At final evaluations, the mean TARM was 220.5+/-43.9 degrees (range 30 degrees to 260 degrees ). The results were excellent in 25 patients (58.1%), good in 12 patients (27.9%), fair in five patients (11.6%), and poor in one patient (2.3%). The mean loss of grip strength was 5.2+/-7.3%. The mean Quick-DASH score was 2.0+/-2.8 (range 0 to 11). All fractures were united. Ten patients had major complications (23.2%), which included extensor tenosynovitis and plate-related discomfort requiring plate removal in four patients (9.3%), and less than 180 degrees of TARM in six patients (14%). CONCLUSION: Low-severity metacarpal fractures can be treated successfully with open reduction and low-profile plate fixation, allowing early and safe functional use.

Magnetic resonance imaging findings of the proximal metacarpus in Quarter Horses used for cutting: Retrospective analysis of 32 horses 2009-2012.

BACKGROUND: Injury to the proximal suspensory ligament is a common cause of lameness in cutting horses. Radiographic and ultrasonographic imaging of lesions responsible for lameness can provide ambiguous results. MRI provides the most comprehensive diagnostic imaging evaluation of lesions specifically affecting cutting horses. OBJECTIVES: To describe the distribution and severity of bone and soft tissue lesions present in the proximal metacarpus of Quarter Horse cutting horses and to assess the impact of these lesions on return to competition. STUDY DESIGN: Retrospective case series. METHODS: Retrospective analysis of 32 cutting horses referred for MRI of the proximal metacarpus between 2009 and 2012 with a 2-year follow-up period. MRI studies were evaluated by a board-certified veterinary radiologist; the severity of lesions was graded from 0 (absent) to 3 (severe). RESULTS: A total of 20 right and 24 left forelimbs (12 bilateral studies) of 32 horses were evaluated. The most common findings were: third metacarpal (McIII) sclerosis at the proximal suspensory ligament (PSL) origin (42/44), McIII resorption at the PSL origin (32/44), PSL dorsal margin fibre irregularity (30/44) and McIII bone contusion (22/39). Of the 30 horses, 22 horses successfully returned to competition, irrespective of severity of injury. Strong correlation exists between the degree of resorption in the palmar cortex of proximal McIII, degree of McIII sclerosis and severity of dorsal margin fibre irregularity. MAIN LIMITATIONS: Statistical significance was limited by small study population. Further analysis of prognosis was limited by availability of comprehensive medical records. CONCLUSIONS: Cutting horses with proximal metacarpal pain have significant pathological change within the proximal suspensory ligament and its enthesis on the palmar cortex of McIII. Severity of lesions and degree of lameness at the time of diagnosis does not influence return to performance. Accurate diagnosis of proximal metacarpal lesions based on MRI offers clinicians the capacity to select treatment protocols targeted to each disease process.

Subchondral bone microdamage accumulation in distal metacarpus of Thoroughbred racehorses.

BACKGROUND: Microdamage accumulation leads to subchondral bone injury and/or fracture in racehorses. An understanding of this process is essential for developing strategies for injury prevention. OBJECTIVES: To quantify subchondral bone microdamage in the third metacarpal bone of Thoroughbred racehorses at different stages of the training cycle. STUDY DESIGN: Cross-sectional. METHODS: Bone blocks from the palmar aspect of the medial condyles of third metacarpal bones from 46 racing Thoroughbred horses undergoing post-mortem were examined with micro computed tomography (microCT) to detect calcified microcracks, and light microscopy to quantify bulk stained microcracks. Racing and training histories were obtained for comparison with microdamage data using regression modelling. RESULTS: Subchondral bone microcracks were observed in all bones with at least one method. Microdamage grade was greater in older horses, levelling-off for horses 5 years and older (quadratic term P = 0.01), and with lower bone material density in the parasagittal groove (P = 0.02). Microcrack density was higher in older horses (P = 0.004), and with higher bone volume fraction (BV/TV) in the parasagittal groove in horses in training (interaction effect, P = 0.01) and lower in horses resting from training (P = 0.02). MAIN LIMITATIONS: Cross-sectional data only. Incomplete detection of microdamage due to the limits of resolution of microCT and lack of three-dimensional imaging with microscopy. Multicollinearity between variables that indicated career progression (e.g. age, number of career starts, duration of training period) was detected. CONCLUSIONS: Fatigue damage in the distal metacarpal subchondral bone is common in Thoroughbred racehorses undergoing post-mortem and appears to accumulate throughout a racing career. Reduced intensity or duration of training and racing and/or increased duration of rest periods may limit microdamage accumulation. Focal subchondral bone sclerosis indicates the presence of microdamage.