Patient-Experience of Trapeziectomy for Trapeziometacarpal Osteoarthritis in Wide-Awake Local Anesthesia no Tourniquet, 2-Year Follow-up.

PURPOSE OF THE STUDY: The purpose of this study was to assess the patient experience of trapeziectomy under WALANT for trapeziometacarpal joint (TMJ) osteoarthritis (OA) in a prospective study with 2-year follow-up. MATERIAL AND METHODS: The study included 23 patients with TMJ OA undergoing trapeziectomy with WALANT. All patients were seen by a hand therapist preoperatively and at 3, 12, and 24 months postoperatively. At each visit, VAS pain scores, thumb range of motion, grip strength, and Disabilities of the Arm, Shoulder and Hand (DASH) score were assessed. The Picker Patient Experience (PPE-15) questionnaire was administered within 2 weeks of surgery. RESULTS: All 23 patients completed the PPE-15 questionnaire. Their mean age was 64 years. The 21 patients who remained at the 24-month follow-up all said they would choose the same anaesthesia method again. At this follow-up, VAS pain scores, thumb range of motion, key pinch grip and DASH scores had improved significantly, while thumb opposition and hand grip strength remained largely unchanged. The majority of patients felt well informed before and during the procedure, and all patients rated pain relief as good or satisfactory. Nearly 40% of patients reported receiving inadequate information about the postoperative medications. DISCUSSION: Patients have a positive attitude to trapeziectomy with WALANT, and seem to prefer WALANT over other methods of anaesthesia. Trapeziectomy with WALANT for TMJ OA is a safe procedure and appears to give a functional outcome similar to trapeziectomy under general anaesthesia. CONCLUSIONS: Trapeziectomy with WALANT for TMJ OA is safe, preferred by patients and has similar clinical outcome as trapeziectomy in general anesthesia. KEY WORDS: trapeziectomy, osteoarthritis, WALANT.

Radiomorphometric analysis of the metapodial bones in the Scottish fold cats.

Scottish Fold cats (Felis catus, Linnaeus 1758) are one of the most well-known and popular cat breeds in the world, characterized by their folded ears attached to the head. Very frequently, cats fall prey of different trauma and accidents that can cause bone fractures especially in the metapodial bones. The method of radiometry is used in veterinary practice to visualize and measure different parts of the animal skeleton. The aim of this study was to assess the linear parameters derived from radiographic images of the metacarpals and metatarsals in Scottish Fold cats and additionally detecting potential sexual dimorphism. Radiographic images of 24 adult Scottish Fold cats (12 male and 12 females) of different ages and weights were analysed. Six linear measurements of the metapodial bones were evaluated to investigate any differences between the sexes. The linear radiometric measurements of the five metacarpals (MC1-5) and the four metatarsals (MT2-5) bones were larger in male metapodial bones than that of female cats. The maximum length (Ml) of the MC1 and MC2 was statistically different between sex, respectively, (p = 0.001) and (p = 0.05). The others metacarpal bones were different in mostly all linear parameters but not statistically significant. The most significant differences between sexes were observed in the parameter of width proximal end (Wp) of MC1-3 (p = 0.001) and MC4 (p = 0.05). More statistical different was MT2 and less MT3. The linear parameter of Bd of the MT4 was the most different statistically between sex (p = 0.001). The results of the study will be useful in function of comparative anatomy, in veterinary clinical practice, in zoo archaeology and in the veterinary forensic investigation.

Roles of collagen cross-links and osteon collagen/lamellar morphotypes in equine third metacarpals in tension and compression tests.

Many bones experience bending, placing one side in net compression and the other in net tension. Because bone mechanical properties are relatively reduced in tension compared with compression, adaptations are needed to reduce fracture risk. Several toughening mechanisms exist in bone, yet little is known of the influences of secondary osteon collagen/lamellar 'morphotypes' and potential interplay with intermolecular collagen cross-links (CCLs) in prevalent/predominant tension- and compression-loaded regions. Paired third metacarpals (MC3s) from 10 adult horses were prepared for mechanical testing. From one MC3/pair, 5 mm cubes were tested in compression at several mid-shaft locations. From contralateral bones, dumbbell-shaped specimens were tested in tension. Hence, habitual/natural tension- and compression-loaded regions were tested in both modes. Data included: elastic modulus, yield and ultimate strength, and energy absorption (toughness). Fragments of tested specimens were examined for predominant collagen fiber orientation (CFO; representing osteonal and non-osteonal bone), osteon morphotype score (MTS, representing osteonal CFO), mineralization, porosity and other histological characteristics. As a consequence of insufficient material from tension-tested specimens, CCLs were only examined in compression-tested specimens (HP, hydroxylysylpyridinoline; LP, lysylpyridinoline; PE, pentosidine). Among CCLs, only LP and HP/LP correlated significantly with mechanical parameters: LP with energy absorption, HP/LP with elastic modulus (both r=0.4). HP/LP showed a trend with energy absorption (r=-0.3, P=0.08). HP/LP more strongly correlated with osteon density and mineralization than CFO or MTS. Predominant CFO more strongly correlated with energy absorption than MTS in both testing modes. In general, CFO was found to be relatively prominent in affecting regional toughness in these equine MC3s in compression and tension.

Effects of a manganese complex with lysine and glutamic acid on growth performance, manganese deposition, and emission, antioxidant capacity and metacarpal strength in weaned piglets.

The present study sought to assess the effects of manganese complexes with lysine and glutamic acid (Mn-LG) as manganese (Mn) sources on growth performance, trace element deposition, antioxidant capacity, and metacarpal strength in weaned piglets. The study involved 288 healthy Duroc × Landrace × Yorkshire piglets that were weaned at 25 to 28 d of age and weighed 8.66 ±â€…0.96 kg. These piglets were randomly divided into six groups: a control group (Mn-LG-0, receiving a basal diet without Mn supplementation), a Mn sulfate group (basal diet supplemented with 40 mg·kg-1 diet of Mn, Mn-S-40 group), and four Mn-LG groups (Mn-LG-20, Mn-LG-40, Mn-LG-60, Mn-LG-80, supplemented with 20, 40, 60, and 80 mg·kg-1 Mn from Mn-LG in the basal diet). Grouping began at weaning on the 0th day of the experiment. The corn-soybean-based basal diet during the early (days 0 to 14) and late (days 15 to 42) phases of the experiment contained 20.88 and 30.12 mg·kg-1 Mn, respectively. Blood samples were collected on days 14 and 42, and pigs were sacrificed for sample collection on day 42. The results indicated no significant differences in average daily gain, average daily feed intake, or feed-to-gain ratio among the groups (P > 0.05). The diarrhea rates of all Mn-LG groups and the Mn-S-40 group were significantly lower in the 0 to 14 d and during the entire experimental period than in the Mn-LG-0 group (P < 0.001). The Mn-LG-40 group exhibited a significant increase in liver Mn concentration and serum Mn superoxide dismutase (Mn-SOD) activity on day 42 (P < 0.01), as well as a significant decrease in fecal Mn concentration (P < 0.05), compared to those of the Mn-S-40 group. Significant differences (P < 0.05) were detected in the serum, liver, and fecal Mn concentrations, as well as in the serum and liver Mn-SOD activity, across the different Mn-LG groups. The serum and fecal Mn concentrations and serum Mn-SOD activity increased linearly or quadratically (P < 0.01) with increasing Mn-LG supplementation. No significant differences (P > 0.05) were found in kidney, heart, or metacarpal bone Mn concentrations or in bone strength indices. In summary, compared with the Mn-LG-0 diet, dietary supplementation with Mn-LG enhanced serum Mn deposition and Mn-SOD activity and decreased the incidence of diarrhea. Additionally, the fecal Mn concentration was lower in the Mn-LG group than in the inorganic group at equivalent dosages.

This research explored the effects of a manganese complex containing lysine and glutamic acid (Mn-LG) on various health parameters in weaned piglets. Utilizing samples of 288 piglets, the study investigated how Mn-LG supplementation influences growth performance, Mn deposition and emission, antioxidant capacity, and metacarpal strength. Key findings include an increase in serum Mn levels and Mn superoxide dismutase (Mn-SOD) activity, a reduction in diarrhea incidence, and no significant effects in bone strength indices in piglets receiving Mn-LG. Additionally, the fecal Mn concentration was notably lower in the Mn-LG group than in the group receiving inorganic Mn at equivalent dosages.

Metacarpal Fracture Fixation with Intramedullary Screws.

Background: Intramedullary screws (IMS) have become a viable option for metacarpal fracture fixation. To further appraise their utility, this study assessed clinical and patient-reported short- and medium-term outcomes of IMS fixation for extra-articular metacarpal fractures. Methods: A retrospective cohort study was performed in a series of 32 patients (with a total of 37 fractures) who underwent metacarpal fracture fixation over a 42-month period between January 2020 and July 2023. Results: Mean time for return to work was 39.8 days; mean time for return to full function was 88.4 days; total active motion was 250.7° (range: 204.9-270.9); Quick Disabilities of the Arm, Shoulder and Hand score was 2.3 (range: 0-22.7); mean visual analogue pain score was 0.9 out of 10 (range: 0-6) and a single complication was observed. Conclusions: The use of IMS in metacarpal fracture fixation is a practicable surgical option. IMS fixations yields a satisfactory duration for return to function, good postoperative range of movement, modest pain scores and low rates of complications. Level of Evidence: Level IV (Therapeutic).

The mysteries of DNA preservation in bone: A comparative study of petrous bones and metacarpal epiphyses using ATR-FTIR spectroscopy.

A comparative analysis of 26 petrous bones and epiphyses of metacarpals from the Second World War era revealed no significant differences in DNA yield or success in STR typing. This unexpected parity in DNA preservation between the petrous bone, a renowned source of endogenous DNA in skeletal remains, and the epiphyses of metacarpals, which are porous and susceptible to taphonomic changes, is surprising. In this study, we introduced ATR-FTIR spectroscopy as an approach to unravel the correlation between bone molecular structure and DNA preservation. Metacarpals and petrous bones with same taphonomic history were sampled and prepared for DNA analyses. While one portion of the sample was used for DNA analysis, the other underwent ATR-FTIR spectroscopic examination. The normalized spectra and FTIR indices between the epiphyses of metacarpals and petrous bones were compared. Because the taphonomic history of the remains used is relatively short and stable, the ATR-FTIR spectroscopy unveiled subtle structural differences between the two bone types. Petrous bones exhibited higher mineralization, whereas epiphyses contained more organic matter. The unexpected preservation of DNA in the epiphyses of metacarpals can likely be attributed to the presence of soft tissue remnants within the trabeculae. Here observed differences in the molecular structure of bones indicate there are different mechanisms enabling DNA preservation in skeletal tissues.

Biomechanical analysis of plate versus K-wire fixation for metacarpal shaft fractures with wedge-shaped bone defects.

BACKGROUND: Metacarpal shaft fracture is a common type of hand fracture. Numerous studies have explored fixing transverse fractures in the midshaft of the metacarpal bone. However, this section of the metacarpal bone is often susceptible to high-energy injury, resulting in comminuted fracture or bone loss. In such cases, wedge-shaped bone defects can develop in the metacarpal shaft, increasing the difficulty of performing fracture fixation. Notably, the research on this type of fracture fixation is limited. This study compared the abilities of four fixation methods to fix metacarpal shaft fractures with wedge-shaped bone defects. METHODS: In total, 28 artificial metacarpal bones were used. To create wedge-shaped bone defects, an electric saw was used to create metacarpal shaft fractures at the midshaft of each bone. The artificial metacarpal bones were then divided into four groups for fixation. The bones in the first group were fixed with a dorsal locked plate (DP group), those in the second group were fixed with a volar locked plate (VP group), and those in the third group were fixed by combining dorsal and volar locked plates (DP + VP group), and those in the fourth group were fixed with two K-wires (2 K group). Cantilever bending tests were conducted using a material testing machine to measure yielding force and stiffness. The four groups' fixation capabilities were then assessed through analysis of variance and Tukey's test. RESULTS: The DP + VP group (164.1±44.0 N) achieved a significantly higher yielding force relative to the 2 K group (50.7 ± 8.9 N); the DP group (13.6 ± 3.0 N) and VP group (12.3 ± 1.0 N) did not differ significantly in terms of yielding force, with both achieving lower yielding forces relative to the DP + VP group and 2 K group. The DP + VP group (19.8±6.3 N/mm) achieved the highest level of stiffness, and the other three groups did not differ significantly in terms of stiffness (2 K group, 5.4 ± 1.1 N/mm; DP group, 4.0 ± 0.9 N/mm; VP group, 3.9 ± 1.9 N/mm). CONCLUSIONS: The fixation method involving the combined use of dorsal and volar locked plates (DP + VP group) resulted in optimal outcomes with respect to fixing metacarpal shaft fractures with volar wedge bone defects.

Subchondral bone fatigue injury in the parasagittal condylar grooves of the third metacarpal bone in thoroughbred racehorses elevates site-specific strain concentration.

Condylar stress fracture of the distal end of the third metacarpal/metatarsal (MC3/MT3) bones is a major cause of Thoroughbred racehorse injury and euthanasia worldwide. Functional adaptation to exercise and fatigue damage lead to structural changes in the subchondral bone that include increased modeling (resulting in sclerotic bone tissue) and targeted remodeling repair (resulting in focal resorption spaces in the parasagittal groove). Whether these focal structural changes, as detectable by standing computed tomography (sCT), lead to elevated strain at the common site of condylar stress fracture has not been demonstrated. Therefore, the goal of the present study was to compare full-field three-dimensional (3D) strain on the distopalmar aspect of MC3 bone specimens with and without focal subchondral bone injury (SBI). Thirteen forelimb specimens were collected from racing Thoroughbreds for mechanical testing ex vivo and underwent sCT. Subsequently, full-field displacement and strain at the joint surface were determined using stereo digital image correlation. Strain concentration was observed in the parasagittal groove (PSG) of the loaded condyles, and those with SBI in the PSG showed higher strain rates in this region than control bones. PSG strain rate in condyles with PSG SBI was more sensitive to CT density distribution in comparison with condyles with no sCT-detectable injury. Findings from this study help to interpret structural changes in the subchondral bone due to fatigue damage and to assess risk of incipient stress fracture in a patient-specific manner.

Equine skeletal scintigraphy: Comparing lesion detection ability of methylene diphosphonate and hydroxymethylene diphosphonate in the caudal cervical and proximal metacarpal/metatarsal regions.

BACKGROUND: Data regarding the lesion detection ability of different radiotracers are lacking in equine bone scintigraphy. METHODS: In this prospective study, hydroxymethylene diphosphonate (HMDP) and methylene diphosphonate (MDP) were compared in horses with increased radiopharmaceutical uptake either in the caudal cervical region (CS group) or in the proximal metacarpal/metatarsal region (PMR group). Region of interest analysis was used to determine normal bone-to-soft tissue ratios, lesion-to-normal bone ratios and lesion-to-soft tissue ratios. Qualitative scoring and total count rates were recorded for each image. RESULTS: A total of 213 scintigrams were included. Within the PMR group, there were significantly higher lesion-to-normal bone ratios for MDP compared with HMDP (p = 0.02). In the CS group, normal bone-to-soft tissue ratios were significantly higher for HMDP (p = 0.01). The interobserver agreement with regard to the qualitative assessment of the scintigrams was poor. LIMITATION: Paired studies, comparing the different radiotracers in the same patient, were not feasible. CONCLUSION: This study revealed minor differences between the two radiotracers, although these have no practical implications. Both radiopharmaceuticals are well suited for detecting lesions at the investigated sites using equine bone scintigraphy.

Morphological and radiographic studies on the Manus region in the Arabian one-humped camel (Camelus dromedaries).

The study aims to analyse the normal anatomical and radiographical features of the Manus of the southern Aswanian-adapted Arabian one-humped camel, providing crucial data for diagnosing and treating various ailments. Our study was applied to 10 cadaver forelimbs of adult male one-humped camels (4-5 years old) for an explanation of the gross anatomy of the bones of the Manus region from under the carpal bones by using traditional techniques, including the gross anatomical, radiographic and x-ray (at the dorsopalmar and lateral planes) of the preparation of Manus bones. Our results showed that the large fused (third and fourth) metacarpal bones, in which the fusion extended along the entire length of the bone except at the distal end, diverged to form separate articulations with cross-ponding digits. As described in all ruminant species, especially the camel, there were two digits, and each digit consisted of three phalanges and two proximal sesamoid bones. Our radiographic x-ray data revealed that the complete radiopaque septum that completely divided the medullary cavity into two separate parts was clear from the dorsopalmar view, while the lateral view showed the proximal sesamoid bones that were placed over each other and located palmar to the head of the large metacarpal bone. In conclusion, our study reveals the adaptations of the Arabian one-humped camel to Egyptian conditions, aiding in the early diagnosis of lameness and digit problems and enabling veterinarians and camel owners to better address these issues, thereby improving the overall health and well-being of these animals.

Clinical analysis of 1301 children with hand and foot fractures and growth plate injuries.

BACKGROUND: Fractures of hands and feet are common in children, but relevant epidemiological studies are currently lacking. We aim to study the epidemiological characteristics of hand and foot fractures and growth plate injuries in children and provide a theoretical basis for their prevention, diagnosis, and treatment. METHODS: We retrospectively analyzed the data of children with hand and foot fractures who were hospitalized at Shenzhen Children's Hospital between July 2015 and December 2020. Data on demographic characteristics, fracture site, treatment method, etiology of injury, and accompanying injuries were collected. The children were divided into four age groups: infants, preschool children, school children, and adolescents. The fracture sites were classified as first-level (the first-fifth finger/toe, metacarpal, metatarsal, carpal, and tarsal) and second-level (the first-fifth: proximal phalanx, middle phalanx, distal phalanx, metacarpal, and metatarsal) sites. The changing trends in fracture locations and injury causes among children in each age group were analyzed. RESULTS: Overall, 1301 children (1561 fractures; 835 boys and 466 girls) were included. The largest number of fractures occurred in preschool children (n = 549, 42.20%), with the distal phalanx of the third finger being the most common site (n = 73, 15.57%). The number of fractures in adolescents was the lowest (n = 158, 12.14%), and the most common fracture site was the proximal phalanx of the fifth finger (n = 45, 29.61%). Of the 1561 fractures, 1143 occurred in the hands and 418 in the feet. The most and least common first-level fracture sites among hand fractures were the fifth (n = 300, 26.25%) and first (n = 138, 12.07%) fingers, respectively. The most and least common first-level foot fracture locations were the first (n = 83, 19.86%) and fourth (n = 26, 6.22%) toes, respectively. The most common first-level and second level etiologies were life related injuries (n = 1128, 86.70%) and clipping injuries (n = 428, 32.90%), respectively. The incidence of sports injuries gradually increased with age, accounting for the highest proportion in adolescents (26.58%). Hand and foot fractures had many accompanying injuries, with the top three being nail bed injuries (570 cases, 36.52%), growth plate injuries (296 cases, 18.96%), and distal severed fracture (167 cases, 10.70%). Among the 296 growth plate injuries, 246 occurred on the hands and 50 on the feet. CONCLUSIONS: In contrast to previous epidemiological studies on pediatric hand and foot fractures, we mapped the locations of these fractures, including proximal, shaft, distal, and epiphyseal plate injuries. We analyzed the changing trends in fracture sites and injury etiologies with age. Hand and foot fractures have many accompanying injuries that require attention during diagnosis and treatment. Doctors should formulate accident protection measures for children of different ages, strengthen safety education, and reduce the occurrence of accidental injuries.

Metacarpal Small Incision for Carpal Tunnel Syndrome.

Endoscopic carpal tunnel release (ECTR) techniques have been established as a successful treatment for carpal tunnel syndrome and have proven equally effective as traditional open carpal tunnel release (OCTR) techniques in relieving pain and numbness. However, patients who undergo OCTR are more likely to experience scar tenderness and pillar pain and take longer to return to work. We present here a method of metacarpal small incision for carpal tunnel release (MSICTR) as a safe, reliable, cost-effective alternative surgical decompression of the median nerve of the wrist. This technique utilizes a metacarpal small incision and direct visualization of the median nerve and carpal tunnel contents, reducing the risk of permanent injury and neurasthenia when compared to traditional OCTR. MSICTR is also suitable for the examination of the median nerve, surrounding tendon sheath, or space-occupying lesions. MSICTR is associated with shorter operation times, less postoperative pain, faster recovery, and improved cosmetic results when compared to traditional OCTR. Therefore, MSICTR is an effective surgical decompression of the median nerve for the treatment of carpal tunnel syndrome.

Evaluation of treatment processes in childhood fifth metacarpal bone (Boxer) fractures with QuickDASH scoring system.

OBJECTIVE: Metacarpal fractures are one of the most common orthopedic injuries seen in emergency departments. Despite this, only a few data have been published about the epidemiology of metacarpal fractures. Simple radiographs are the standard imaging modality used to diagnose boxer fractures and determine the degree of angulation. Fractures and angulations should be identified by anteroposterior and lateral radiographs. The aim of this study was to follow the healing after closed reduction of fifth metacarpal neck fractures in a pediatric population using the QuickDASH score to determine whether it results in clinically significant improvement. SUBJECTS AND METHODS: Between 2020 and 2022, our clinical record database for all metacarpal fractures treated at our institution was searched retrospectively every month. Children aged 18 years and younger with fifth metacarpal neck fractures treated with closed reduction and immobilization in our tertiary care emergency clinic were retrospectively reviewed. RESULTS: 52 pediatric patients were included in the study. The mean age at the time of injury was 14.04 years (SD=2.10, range=10-18 years). 92.30% (n=48) of the patients were male, and 7.70% (n=4) were female. CONCLUSIONS: Accurate diagnosis and appropriate treatment are crucial in the management of childhood fifth metacarpal fractures to ensure proper healing, prevent long-term complications, and facilitate optimal functional recovery.

Early Return of Motion in Patients With Intramedullary Screw Placement for Metacarpal and Phalangeal Fracture Fixation.

INTRODUCTION: Hand fractures are associated with significant morbidity. Current management standards often result in prolonged immobilization, stiffness, and delayed return to functional use. Intramedullary (IM) compression screws offer minimal soft tissue disruption and early postoperative active motion. In this study, we describe our outcomes after intraosseous fracture fixation using IM cannulated headless screws for a multitude of fracture patterns. METHODS: This study is a retrospective review of patients who underwent IM screw placement for fixation of metacarpal and phalangeal fractures by a single surgeon from 2017 to 2022. Data were collected to include patient demographics, fracture details, postoperative complications, and follow-up. Time to range of motion and return to unrestricted motion was recorded. RESULTS: There were 69 patients with 92 fractures (n = 54 metacarpal, n = 38 phalanx). The median patient age was 45 years (range, 18-89 years) with 75.4% males. Majority presented with a single fracture (n = 50, 72.5%), and 38 patients (55.1%) had open fractures. Small finger was the most affected digit (n = 35, 37.6%). The median time to allow range of motion from surgery was 8.7 days (interquartile range, 0-32) with 32 days (interquartile range, 10-62) for unrestricted use of the hand. Thirty-five patients (50.7%) were allowed controlled motion from the first postoperative day. One patient had loss of reduction requiring reintervention for hardware removal, and 1 patient had superficial skin infection managed with oral antibiotics. CONCLUSIONS: Our findings indicate that the IM screw provides reliable fixation for a wide variety of fracture patterns with a low complication rate and offers early return to functional use.

Influence of microarchitecture on stressed volume and mechanical fatigue behaviour of equine subchondral bone.

Fractures of the equine metacarpophalangeal (MCP) joint are among the most common and fatal injuries experienced by racehorses. These bone injuries are a direct result of repetitive, high intensity loading of the skeleton during racing and training and there is consensus that they represent a mechanical fatigue phenomenon. Existing work has found the fatigue life of bone to be strongly determined by bone microarchitecture and the resulting stressed volume (i.e., the volume of bone stressed above assumed yield). The purpose of this study was to quantify the influence of bone microarchitecture on the mechanical fatigue behaviour of equine subchondral bone from the MCP joint across a wide variety of sample types. Forty-eight subchondral bone samples were prepared from the third metacarpal (MC3) and proximal phalanx (P1) of 8 horses and subsequently imaged using high resolution micro-computed tomography (µCT) to quantify microarchitectural features of interest, including bone volume fraction, tissue mineral density, pore size, pore spacing, and pore number. Samples were cyclically loaded in compression to a stress of 70 MPa, and fatigue life was defined as the number of cycles until failure. Finite element models were created from the µCT images and used to quantify stressed volume. Based on the expected log point-wise predictive density, stressed volume was a strong predictor of fatigue life in both the MC3 and P1. A regional analysis indicated fatigue life was more strongly associated with bone volume fraction in the superficial (r2 = 0.32, p < 0.001) and middle (r2 = 0.70, p < 0.001) regions of the subchondral bone, indicating the prominent role that the cortical plate played in the fatigue resistance of equine subchondral bone. By improving our understanding of the variance in fatigue life measurements, this research helps clarify the underlying mechanisms of the mechanical fatigue process and provides a basic understanding of subchondral bone injuries in the equine fetlock joint.

The 'Shish-Kebab technique' in intra-articular fractures of the hamate body and concomitant 4th metacarpal base fracture.

PURPOSE: Hamate fractures are infrequent and often overlooked wrist injuries. Our objective is to present the Shish-Kebab method, a surgical approach utilized in the treatment of intra-articular Hamate body fractures occurring concurrently with fourth metacarpal base fractures and dislocations. METHODS: This study was conducted at a single-center using a prospective design. It included patients aged 16-65 with Kim Type IIB fractures affecting the dominant side. Patients with the same features of fracture and carpometacarpal (CMC) instability findings were divided into two groups according to the success of the closed reduction procedure. In the conservative group (8 patients), all fractures and instability findings were successfully resolved with closed reduction and a short arm plaster cast. The surgical group (8 patients), comprising those requiring open reduction and internal fixation, underwent the application of the 'shish kebab' method. RESULTS: At the 6th and 12th week follow-ups, no significant differences were observed between the groups concerning pVAS and QuickDash scores. However, upon examining the QuickDash scores, a statistically significant difference emerged between the 6th and 12th weeks within both the conservative (p = 0.017) and surgical (p = 0.012) groups in the intragroup analysis. Grip strength, measured as 83.78% of the contralateral side in the surgical group and 79.51% in the conservative group, did not exhibit a statistically significant difference (p = 0.462). CONCLUSION: In the management of Hamate body intra-articular fractures and accompanying fourth metacarpal base fracture dislocations, good clinical results can be achieved with the 'Shish-Kebab' method in cases where closed reduction is unsuccessful.

Novel Mini-Invasive Surgical Technique for Treating Fifth Metacarpal Neck Fractures: A Case Report.

BACKGROUND Fracture of the fifth metacarpal of the hand is due to trauma to the clenched fist. The non-displaced fracture can be treated by splinting and immobilization, but fracture dislocation requires individualized management to ensure the return of function. The Jahss maneuver for reduction of volar displaced metacarpal neck fractures involves flexion of the metacarpophalangeal and proximal interphalangeal joint at 90°, with the proximal phalanx used to reduce the metacarpal head. This report is of a 25-year-old male Italian pianist with a displaced fifth metacarpal neck fracture successfully treated by reduction using the Jahss maneuver and K-wire attachment of subchondral bone to the metacarpal. CASE REPORT A pianist presented with a trauma to his right hand due to punching a wall. Radiograph images demonstrated an angulated, displaced right fifth neck fracture. A specific approach was decided, considering the complexity of the musical movements and the patient's performance needs. After fracture's reduction by the Jahss maneuver, 2 retrograde cross-pinning K-wires were inserted at the subchondral bone of the metacarpal head. Healing under splinting was uneventful, and the K-wires were removed after 45 days. At 4 months after surgery, the patient had complete recovery of both range of motion and strength. CONCLUSIONS Our technique avoided piercing the metacarpophalangeal joint capsule, preventing extensor tendon damage, dislocation, instability, and pain and retraction of the extensor cuff. This novel mini-invasive technique successfully achieved early metacarpophalangeal joint motion, joint stability, and complete recovery of movements in all planes.

Mechanical response of local regions of subchondral bone under physiological loading conditions.

Most fractures in the third metacarpal bone of equine athletes occur due to repeated cycles of high load magnitudes and are commonly generated during fast-training workouts. These repetitive loads may induce changes in the microstructure and mechanical properties that can develop into subchondral bone (SCB) injuries near the articular surface. In this study, we investigated the fatigue behaviour of local regions in SCB (near the articular surface i.e., 2 mm superficial SCB and the underlying 2 mm deeper SCB) under a simulated fast-training workout of an equine athlete. A fatigue test on SCB specimens was designed to simulate the fast-training workout, which comprised of repeated load cycles with varying load magnitude, representing the varying gait speed during a fast-training workout. The fatigue test was applied three times to each of the five cylindrical SCB specimens harvested from the left and right metacarpal condyles of five thoroughbred racehorses). All specimens completed at least one fatigue test. Three specimens completed all three fatigue tests with no visible cracks identified with Micro-CT scans. The other two specimens failed in the second fatigue test, and cracks were identified with Micro-CT scans in the various local regions. Using Digital Image Correlation (DIC) analysis, we found that in the local regions of all specimens, modulus decreased between load cycles corresponding to 68 and 93 MPa load magnitudes (equivalent to the fastest gallop speed). Wherein specimens that failed exhibited a greater decrease in modulus (in superficial SCB by 45.64 ± 5.66% and in deeper SCB by -36.85 ± 10.47% (n = 2)) than those not failed (in superficial SCB by -7.45 ± 14.62% and in deeper SCB by -5.67 ± 7.32% (n = 3)). This has provided evidence that the loads on SCB at galloping speeds are most likely to produce fatigue damage and that the damage induced is localised. Furthermore, one of the failed specimens exhibited a peak in the tensile strain rather than compressive strain in the superficial region with a rapid decrease in modulus. In addition, the superficial region of all specimens exhibited greater residual tensile strain than that of the deeper region.