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American Journal of Veterinary Research Aug 2009To compare biomechanical strength, interface quality, and effects of bone healing in bone-implant interfaces that were untreated or treated with calcium phosphate cement... (Clinical Trial)
Clinical Trial
OBJECTIVE
To compare biomechanical strength, interface quality, and effects of bone healing in bone-implant interfaces that were untreated or treated with calcium phosphate cement (Ca-cement), magnesium phosphate cement (Mg-cement), or polymethylmethacrylate (PMMA) in horses.
ANIMALS
6 adult horses.
PROCEDURES
4 screw holes were created (day 0) in each third metacarpal and third metatarsal bone of 6 horses. In each bone, a unicortical screw was placed in each hole following application of Ca-cement, Mg-cement, PMMA, or no treatment (24 screw holes/treatment). Screws were inserted to 2.82 N m torque. Horses were euthanized and bones were harvested at day 5 (16 screw holes/treatment) or day 182 (8 screw holes/treatment). Radiography, biomechanical testing, histomorphometry, and micro-computed tomography were performed to characterize the bone-implant interfaces.
RESULTS
Use of Mg-cement increased the peak torque to failure at bone-implant interfaces, compared with the effects of no treatment and Ca-cement, and increased interface toughness, compared with the effects of no treatment, Ca-cement, and PMMA. Histologically, there was 44% less Ca-cement and 69% less Mg-cement at the interfaces at day 182, compared with amounts present at day 5. Within screw threads, Ca-cement increased mineral density, compared with PMMA or no treatment. In the bone adjacent to the screw, Mg-cement increased mineral density, compared with PMMA or no treatment. One untreated and 1 Ca-cement-treated screw backed out after day 5.
CONCLUSIONS AND CLINICAL RELEVANCE
In horses, Mg-cement promoted bone-implant bonding and adjacent bone osteogenesis, which may reduce the risk of screw loosening.
Topics: Analysis of Variance; Animals; Bone Cements; Bone Screws; Calcium Phosphates; Fracture Fixation, Internal; Fracture Healing; Horses; Magnesium; Metacarpal Bones; Metatarsal Bones; Osteogenesis; Polymethyl Methacrylate; X-Ray Microtomography
PubMed: 19645577
DOI: 10.2460/ajvr.70.8.964 -
Journal of Biomechanics Sep 2015Characterizing the morphology of the carpometacarpal (CMC) joint bones and how they vary across the population is important for understanding the functional anatomy and... (Comparative Study)
Comparative Study
Characterizing the morphology of the carpometacarpal (CMC) joint bones and how they vary across the population is important for understanding the functional anatomy and pathology of the thumb. The purpose of this paper was to develop a statistical shape model of the trapezium and first metacarpal bones to characterize the size and shape of the whole bones across a cohort of 50. We used this shape model to investigate the effects of sex and age on the size and shape of the CMC joint bones and the articulating surface area of the CMC joint. We hypothesized that women have similar shape trapezium and first metacarpal bones compared to men, following scaling for overall size. We also hypothesized that age would be a significant predictor variable for CMC joint bone changes. CT image data and segmented point clouds of 50 CMC bones from healthy adult men and women were obtained from an ongoing study and used to generate two statistical shape models. Statistical analysis of the principal component weights of both models was performed to investigate morphological sex and age differences. We observed sex differences, but were unable to detect any age differences. Between men and women the only difference in morphology of the trapezia and first metacarpal bones was size. These findings confirm our first hypothesis, and suggest that the women have similarly shaped trapezium and first metacarpal bones compared to men. Furthermore, our results reject our second hypothesis, indicating that age is a poor predictor of CMC joint morphology.
Topics: Adult; Carpometacarpal Joints; Female; Humans; Male; Middle Aged; Radiography; Sex Characteristics; Thumb; Trapezium Bone; Young Adult
PubMed: 26116042
DOI: 10.1016/j.jbiomech.2015.05.031 -
BMC Musculoskeletal Disorders Dec 2013High Resolution-Peripheral Quantitative Computed Tomography (HR-pQCT) is an emerging technology for evaluation of bone quality in Rheumatoid Arthritis (RA). However,...
A customized protocol to assess bone quality in the metacarpal head, metacarpal shaft and distal radius: a high resolution peripheral quantitative computed tomography precision study.
BACKGROUND
High Resolution-Peripheral Quantitative Computed Tomography (HR-pQCT) is an emerging technology for evaluation of bone quality in Rheumatoid Arthritis (RA). However, there are limitations with standard HR-pQCT imaging protocols for examination of regions of bone commonly affected in RA. We developed a customized protocol for evaluation of volumetric bone mineral density (vBMD) and microstructure at the metacarpal head (MH), metacarpal shaft (MS) and ultra-ultra-distal (UUD) radius; three sites commonly affected in RA. The purpose was to evaluate short-term measurement precision for bone density and microstructure at these sites.
METHODS
12 non-RA participants, individuals likely to have no pre-existing bone damage, consented to participate [8 females, aged 23 to 71 y [median (IQR): 44 (28) y]. The custom protocol includes more comfortable/stable positioning and adapted cortical segmentation and direct transformation analysis methods. Dominant arm MH, MS and UUD radius scans were completed on day one; repeated twice (with repositioning) three to seven days later. Short-term precision for repeated measures was explored using intraclass correlational coefficient (ICC), mean coefficient of variation (CV%), root mean square coefficient of variation (RMSCV%) and least significant change (LSC%95).
RESULTS
Bone density and microstructure precision was excellent: ICCs varied from 0.88 (MH2 trabecular number) to .99 (MS3 polar moment of inertia); CV% varied from < 1 (MS2 vBMD) to 6 (MS3 marrow space diameter); RMSCV% varied from < 1 (MH2 full bone vBMD) to 7 (MS3 marrow space diameter); and LSC%95 varied from 2 (MS2 full bone vBMD to 21 (MS3 marrow space diameter). Cortical porosity measures were the exception; RMSCV% varying from 19 (MS3) to 42 (UUD). No scans were stopped for discomfort. 5% (5/104) were repeated due to motion during imaging. 8% (8/104) of final images had motion artifact graded > 3 on 5 point scale.
CONCLUSION
In our facility, this custom protocol extends the potential for in vivo HR-pQCT imaging to assess, with high precision, regional differences in bone quality at three sites commonly affected in RA. Our methods are easy to adopt and we recommend other users of HR-pQCT consider this protocol for further evaluations of its precision and feasibility in their imaging facilities.
Topics: Adult; Aged; Arthritis, Rheumatoid; Clinical Protocols; Female; Healthy Volunteers; Humans; Male; Metacarpal Bones; Middle Aged; Radius; Tomography, X-Ray Computed; Young Adult
PubMed: 24364867
DOI: 10.1186/1471-2474-14-367 -
Hand (New York, N.Y.) Sep 2022It is recommended to have 6 bicortical screws for plate fixation of long bone fractures; however, many metacarpal fractures do not allow 6 screws due to size limitations...
BACKGROUND
It is recommended to have 6 bicortical screws for plate fixation of long bone fractures; however, many metacarpal fractures do not allow 6 screws due to size limitations and proximity of crucial anatomical structures. The purpose of this biomechanical study was to determine whether the mechanical properties of a 4-screw nonlocking construct are noninferior to those of a 6-screw nonlocking construct.
METHODS
Metacarpal sawbones were used to simulate a midshaft, transverse fracture. Nonlocking bicortical screws were placed in the 6-hole plate, and the metacarpals were randomly assigned to 2 equal study groups: (1) 4 screws, 2 on either side of the fracture (4S); and (2) 6 screws, 3 on either side of the fracture (6S). The metacarpals were tested in a cyclic loading mode and load to failure in a cantilever bending mode.
RESULTS
Maximum deflection was significantly higher for 4S compared with 6S. Cyclic root mean square (RMS) was also significantly greater for 4S at 70 and 100 N. There were no statistically significant differences observed between the 2 constructs for maximum bending load, bending stiffness, and cyclic RMS at 40 N. The maximum bending load in 4S and 6S was 245.6 ± 37.9 N and 230.8 ± 41.9 N, respectively; 4S was noninferior and not superior to 6S. Noninferiority testing was inconclusive for bending stiffness.
CONCLUSIONS
A 4-screw bicortical nonlocking construct is noninferior to a 6-screw bicortical nonlocking construct for fixation of metacarpal fractures, which may be advantageous to minimize disruption of soft tissues while maintaining sufficient construct stability.
Topics: Biomechanical Phenomena; Bone Screws; Fracture Fixation, Internal; Fractures, Bone; Hand Injuries; Humans; Metacarpal Bones
PubMed: 33349049
DOI: 10.1177/1558944720974116 -
Journal of Orthopaedic Surgery and... Sep 2023This study aimed to compare the clinical efficacy of microplate trans-carpometacarpal joint fixation and non-trans-carpometacarpal joint fixation in treating fractures...
A comparative study on the clinical efficacy of microplate trans-carpometacarpal joint fixation and non-trans-carpometacarpal joint fixation in treating fractures with dislocation or subluxation of the base of the fourth and fifth metacarpal bones.
BACKGROUND
This study aimed to compare the clinical efficacy of microplate trans-carpometacarpal joint fixation and non-trans-carpometacarpal joint fixation in treating fractures and dislocation or subluxation of the base of the fourth and fifth metacarpal bones.
METHOD
From 2015 to 2021, 100 cases of metacarpal basal fractures with dislocation or subluxation were randomly divided into the trans-carpometacarpal joint fixation group (group A) and non-trans-carpometacarpal joint fixation group (group B). Group A (n = 50) comprised 44 males and 6 females, with an average age of 28.8 ± 6.1 y and an Orthopedic Trauma Association (OTA) fracture classification of type B1 (n = 29) or C1 (n = 21). Group B (n = 50) comprised 45 males and 5 females, with an average age of 28.9 ± 5.7 y and an OTA fracture classification of type B1 (n = 28) or C1 (n = 22). All patients were complicated with dislocation or subluxation. The surgery time, fracture healing time, postoperative handgrip strength, and total active motion (TAM) scores of the ring and little fingers were recorded and compared between the two groups. The clinical efficacy of patients was evaluated using scoring methods such as DASH (disabilities of the arm, shoulder and hand), visual analogue scale (VAS), and Mayo at 3, 6, and 12 months after surgery.
RESULTS
There was no significant difference in the general indexes, surgery time, or fracture healing time between the two groups (P > 0.05). There were no significant differences in handgrip strength and TAM scores of the ring and little fingers between the two groups at 3 and 12 months postoperatively (P > 0.05), but there were significant differences in these indexes 6 months postoperatively (P < 0.05). There were no significant differences in the DASH, VAS, and Mayo scores at 3 and 12 months postoperatively (P > 0.05), but there were significant differences between the two groups in the DASH and Mayo scores (P < 0.05) but not the VAS score (P > 0.05) 6 months postoperatively.
CONCLUSION
In the treatment of fourth and fifth metacarpal basal fractures with dislocation or subluxation, both microplate transarticular fixation and non-transarticular fixation could achieve fracture fixation and healing, and each method had advantages and disadvantages. The clinically appropriate fixation method should be selected according to the experience of the surgeon and the degree and type of fracture and dislocation.
Topics: Male; Female; Humans; Young Adult; Adult; Metacarpal Bones; Carpometacarpal Joints; Hand Strength; Fracture Fixation, Internal; Fractures, Bone; Joint Dislocations; Treatment Outcome; Hand Injuries
PubMed: 37770964
DOI: 10.1186/s13018-023-04225-2 -
Orthopaedics & Traumatology, Surgery &... Dec 2022There appears to be a paucity of knowledge about the biomechanics of locking plates for the fixation of metacarpal shaft fractures. A thorough understanding of the...
BACKGROUND
There appears to be a paucity of knowledge about the biomechanics of locking plates for the fixation of metacarpal shaft fractures. A thorough understanding of the biomechanics of locking plates is needed to apply them correctly, optimize outcomes, and avoid complications. The purpose of this study is to investigate the biomechanics of the fixation of metacarpal fractures using locking plate-screw constructs with different numbers of screws.
HYPOTHESIS
The difference in the number of screws in the locking plate influenced the biomechanical outcome of the metacarpal fracture.
METHODS
Finite element models of third metacarpal fractures with locking plate-screw constructs were established, and the magnitude and distribution of their stresses and displacements were investigated when a vertical load of 100N was applied.
RESULTS
For the metacarpal fracture with a locking plate and screws, the stress in the metacarpal was largely shared by the plate-screw construct. For the plate-screw construct, the stress is concentrated in the area close to the fracture line, and the 6-screw Group has the lowest failure risk since it has the lowest plate stress and the second-lowest screw stress. The implant-bone construct with 8 screws has better biomechanical stability because of minimal displacement, but increased stress on both the metacarpal bone and the screws, leading to increased failure rates.
DISCUSSION
The stresses in the metacarpal were mostly shared by the plate-screw constructs and the screws closest to the fracture line were the most likely to break or loosen. For the implant-bone constructs, the locking plate with 2 screws was the most vulnerable to break or loosen, whereas the locking plate with 6 screws was the least likely to break or loosen. The implant-bone construct with 8 screws had better biomechanical stability, but the stresses in both the metacarpal and the screws were increased, which increased the risk of failure.
LEVEL OF EVIDENCE
IV, basic science study.
Topics: Humans; Finite Element Analysis; Metacarpal Bones; Fracture Fixation, Internal; Bone Plates; Fractures, Bone; Biomechanical Phenomena; Hand Injuries
PubMed: 35643362
DOI: 10.1016/j.otsr.2022.103340 -
Acta Ortopedica Mexicana 2009Multiple carpometacarpal fracture dislocations are rare lesions despite the increased number of high-energy traumatic injuries. These lesions result from high-energy...
Multiple carpometacarpal fracture dislocations are rare lesions despite the increased number of high-energy traumatic injuries. These lesions result from high-energy traumas or, even more frequently, from fall mechanisms involving palmar flexion of the hand. The diagnosis usually requires specific X-ray views to prevent overlooking those lesions. A 27-year-old male presented at the emergency room in our hospital after sustaining a direct trauma on the right hand, in palmar flexion, resulting from a stair fall. The patient had severe inflammation of the dorsal aspect of the hand, pain, limitation, and complete functional disability. X-rays led to diagnosing fracture dislocation of the hamate, capitate and base of the 3rd, 4th, and 5th metacarpal bones. Treatment consisted of closed reduction under fluoroscopic control, fixation with Orthofix threaded nails and placement of a fiberglass cast in functional position for six weeks. The patient's clinical and radiological course was appropriate; healing of the hamate, capitate, and base of the 3rd, 4th and 5th metacarpal bones was attained without necrosis of the carpal bones. The Orthofix threaded nails were removed. After a period of functional rehabilitation the patient course was appropriate, without any functional limitation of the hand joints. This is an unusual lesion with only a few bibliographic references. We think that a specific X-ray study is fundamental to prevent overlooking these lesions. In this case our priority was reconstructing the base to assure articular continuity and stabilization with threaded Orthofix nails, given the high degree of instability of the lesion.
Topics: Adult; Carpometacarpal Joints; Fractures, Bone; Humans; Joint Dislocations; Male; Multiple Trauma; Radiography
PubMed: 19739349
DOI: No ID Found -
Journal of Orthopaedic Research :... Nov 2017Achondroplasia (ACH) is a heritable disorder of endochondral bone formation characterized by disproportionate short stature. Osteogenesis imperfecta (OI) is a heritable...
UNLABELLED
Achondroplasia (ACH) is a heritable disorder of endochondral bone formation characterized by disproportionate short stature. Osteogenesis imperfecta (OI) is a heritable bone and connective tissue disorder characterized by bone fragility. To investigate bone morphology of these groups, we retrospectively reviewed 169 de-identified bone age films from 20 individuals with ACH, 39 individuals with OI and 37 age- and sex-matched controls (matched to historical measurements from the Bolton-Brush Collection). We calculated robustness (Tt.Ar/Le) and relative cortical area (Ct.Ar/Tt.Ar) from measurements of the second metacarpal, which reflect overall bone health. Relative cortical area (RCA) is a significant predictor of fracture risk and correlates with robustness at other sites. Individuals with OI had RCH values above and robustness values below that of the control population. Bisphosphonate treatment did not significantly impact either robustness or RCA. In contrast to that reported in the unaffected population, there was no sexual dimorphism found in OI robustness or relative cortical area. We suggest that the underlying collagen abnormalities in OI override sex-specific effects. Individuals with ACH had robustness values above and RCA values below that of the control population. Sexual dimorphism was found in ACH robustness and RCH values.
CLINICAL SIGNIFICANCE
Identifies morphologic trends in two distinct skeletal dysplasia populations (OI and ACH) to better understand development of bone robusticity and slenderness in humans. Understanding these patterns of bone morphology is important to predict how individuals will respond to treatment and to increase treatment effect. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2392-2396, 2017.
Topics: Achondroplasia; Adolescent; Adult; Aged; Bone Density Conservation Agents; Child; Child, Preschool; Diphosphonates; Female; Humans; Infant; Male; Metacarpal Bones; Middle Aged; Osteogenesis Imperfecta; Radiography; Retrospective Studies; Sex Characteristics; Young Adult
PubMed: 28186356
DOI: 10.1002/jor.23543 -
American Journal of Veterinary Research Dec 2018OBJECTIVE To compare strain at the bone-pin and cast-pin interfaces among 3 transfixation pin-cast constructs applied to equine forelimbs. ANIMALS 15 forelimbs from 15...
OBJECTIVE To compare strain at the bone-pin and cast-pin interfaces among 3 transfixation pin-cast constructs applied to equine forelimbs. ANIMALS 15 forelimbs from 15 adult horses. PROCEDURES Limbs were randomly assigned to 1 of 3 constructs. Centrally threaded positive-profile pins were used for all constructs, and the most distal pin was placed just proximal to the epicondyles of the third metacarpal bone. Construct 1 consisted of two 6.3-mm-diameter pins spaced 4 cm apart at 30° to each other. Construct 2 was the same as construct 1 except the pins were placed 5 cm apart. Construct 3 consisted of four 4.8-mm-diameter pins spaced 2 cm apart and at 10° to one another. An osteotomy was created in the proximal phalanx. Strain gauges were attached to the cast and bone proximal to the pins and adjacent to the osteotomy. Limbs underwent compressive loading until failure. Simplified finite element models of constructs 1 and 3 were created to further evaluate strain and load transfer between the bone and cast. RESULTS Strain did not differ between constructs 1 and 2. Compared with the 2-pin constructs, construct 3 had less strain at the bone-pin interface and more strain at the cast-pin interface, which indicated a greater amount of load was transferred to the cast of the 4-pin construct than the cast of the 2-pin constructs. Finite element modeling supported those findings. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that the 4-pin construct was more effective in unloading the fractured bone than either 2-pin construct.
Topics: Animals; Biomechanical Phenomena; Bone Nails; Forelimb; Fractures, Bone; Horses; Metacarpal Bones; Osteotomy; Random Allocation
PubMed: 30457907
DOI: 10.2460/ajvr.79.12.1287 -
Journal of the American Veterinary... Dec 2019
Topics: Animals; Female; Horse Diseases; Horses; Joints; Lameness, Animal; Metacarpal Bones; Osteochondrosis; Physical Conditioning, Animal
PubMed: 31730432
DOI: 10.2460/javma.255.11.1227