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.

Complex dorsal metacarpophalangeal joint dislocation associated with proximal metacarpal fracture: case report and review of the literature.

INTRODUCTION: Complex dorsal metacarpophalangeal joint (MCPJ) dislocations are uncommon injuries that mainly affect the index finger and are typically caused by a fall on an outstretched hand. It is exceptional for complex MCPJ dislocation to coexist with a distal fracture of the corresponding metacarpal bone. PRESENTATION OF THE CASE: The authors report a case of a 23-year-old man presented to the emergency, with a complex dorsal metacarpophalangeal joint dislocation of the index associated with a distal metacarpal fracture confirmed by imaging. The patient had an open reduction and internal fixation of the proximal metacarpal fracture. The results were satisfying. DISCUSSION: Dorsal MCP joint dislocations are rare, primarily affecting the index and little fingers, and are typically caused by a fall on an outstretched hand. Complex dislocations, characterized by irreducibility, involve structures forming a "noose" around the metacarpal head. Fractures associated with these dislocations are uncommon. Early diagnosis is crucial for better long-term functional outcomes. Radiographic imaging, including three different views, is necessary for accurate diagnosis. Surgery is usually required, with different approaches depending on the case. Arthroscopic techniques can be used when reduction is challenging. Timely surgical intervention yields the best results. Stiffness, osteoarthritis, osteonecrosis, and growth arrest in pediatric cases are the main complications. CONCLUSION: Complex dorsal metacarpophalangeal joint (MCPJ) dislocations are rare. Open reduction is typically necessary for optimal outcomes. Complications such as stiffness, osteoarthritis can arise, emphasizing the importance of accurate diagnosis and appropriate management.

Computed Tomographic Evaluation of the Sagittal Ridge of the Third Metacarpal Bone in Young Thoroughbred Racehorses: A Longitudinal Study.

Metacarpophalangeal joint region pain is a common cause of lameness in racehorses. Radiological abnormalities in the sagittal ridge (SR) of the third metacarpal bone have been associated with joint effusion, lameness and reduced sales prices. The aims were to describe computed tomographic (CT) appearance of the SR in racehorses, and to document the progression of these findings over three assessments. Forty yearlings were enrolled at the first examination (time 0). Re-examinations were performed twice, approximately six months apart on 31 (time 1) and 23 (time 2) horses, respectively. Computed tomographic examinations of both metacarpophalangeal regions were performed with the horses in a standing position. Computed tomographic reconstructions were analysed subjectively and objectively. The mean Hounsfield Unit values (Hus) of eight radial segments and location, size and shape of hypoattenuating lesions were recorded. Mean Hus at time 1 were higher than at time 0. There was no difference between mean HU at times 1 and 2. The mean HU values of the dorsal half were higher in the right forelimbs and in fillies. Hypoattenuation was identified in 33/80 (41.3%) limbs at time 0, in 22/62 (35.5%) limbs at time 1 and in 14/46 (30.4%) limbs at time 2. All hypoattenuations were located in the dorsodistal aspect of the SR. The most common shapes were hypoattenuating lesions elongated proximodistally and those extending towards trabecular bone. An increase in attenuation of the SR occurred in the first six months of training. Hypoattenuating lesions could decrease in size and could resolve during early training. In this population, these lesions were not associated with lameness.

DIETERICH's disease of both the third and the fourth metacarpal head in a teenage boy: case report and review of literature.

Dieterich's disease or avascular osteonecrosis of the metacarpal head is rare and not often described in the literature. It affects typically the middle of metacarpal bones and can occur at all age groups. A case of a teenager with chronic pain of the third and fourth metacarpal head is presented.

The Current Concept and Evidence-Based Practice in the Base of the First Metacarpal Bone Fracture.

Repetitive instances of sudden injuries to the first metacarpal bone can affect thumb movement. These injuries typically occur after vertical impact to the thumb. The treatment for these injuries should focus on restoring the structure and biomechanics of the trapeziometacarpal joint, with surgery being recommended for optimal results. Bennett's fracture involves the bifurcation of the bone into two distinct fragments, characterized by a smaller fragment and a larger counterpart. Rolando fracture is associated with a fracture of the base of the first metacarpal bone, typically divided into three parts. An extra-articular fracture involves the metacarpal bone of the thumb. Conservative treatment outcomes have been found to be unsatisfactory when the fracture is displaced. Therefore, surgery methods such as minimally invasive surgery, open reduction, and arthroscopic surgery have been proven to be effective. Surgical techniques for bone procedures include pin fixation, direct screw fixation, indirect screw fixation, and mini-plate fixation. Additionally, the prognosis of this condition depends on the ability to restore joint mobility during rehabilitation.

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.

Dorsal approach for isolated volar fracture-dislocation of the base of the second metacarpal: A case report.

BACKGROUND: We report a case with the displacement of an articular fracture fragment of the base of the second metacarpal from the ulnar to the volar side, treated via the dorsal approach. The dorsal approach can be a good option not only because it allows direct observation of ligament damage and fixation of bone fragments but also because the thin subcutaneous tissue makes the approach easier. CASE SUMMARY: A 45-year-old man with a right hand injury visited the hospital. A small bone fragment was identified using plain radiography. Lateral radiography revealed the fragment as lying over the volar aspect of the carpometacarpal (CMC) joint. Computed tomography revealed that approximately one-third of the CMC joint surface of the second metacarpal was damaged. We provisionally diagnosed an intra-articular fracture with significant CMC joint instability and performed open reduction and internal fixation. We made a dorsal longitudinal incision over the CMC joint between the second and third metacarpals. The dorsal ligament of the third CMC joint was torn. We thought it had been dislocated to the volar side and spontaneously reduced to that position. There are only few reports of volar dislocation of CMC joint fractures, particularly of the second and third metacarpals; our report is unique as our patient had an intact interosseous ligament between the second and third metacarpals. CONCLUSION: Although past reports have used a palmar approach, the dorsal approach is a good option for these cases.

The Effect of Steroid and Mannitol Combination Treatment on Postoperative Rehabilitation of Multiple Metacarpal Bone Fractures.

Background and Objectives: The expedient resolution of postoperative soft tissue edema is particularly important in hand surgery. Prolonged edema and pain become an obstacle to postoperative rehabilitation, delay return to daily life, and in severe cases, lead to a permanent decrease in range of motion. Based on the common physiology between postoperative hand swelling and complex regional pain syndrome (CRPS), we sought to determine if postoperative mannitol and steroid administration to multiple metacarpal bone fracture patients effectively reduces hand swelling and pain and is beneficial for hand rehabilitation. Materials and Methods: From March 2015 to February 2019, 21 patients who received closed pinning for multiple metacarpal fractures were included in a retrospective cohort study. The control group (n = 11) underwent a routine recovery, while the treatment group (n = 10) received dexamethasone and mannitol injections for five days postoperatively. Serial changes in the degree of pain and fingertip-to-palm distance (FPD) were measured in both groups. The duration from surgery to the initiation of rehabilitation and time to full grip was also compared. Results: Compared to the control, the treatment group showed a faster alleviation of pain scores from the postoperative fifth day (2.91 versus 1.80, p = 0.013), and faster recovery of FPD from postoperative two weeks (3.27 versus 1.90, p = 0.002). Time to physical therapy initiation (6.73 versus 3.80 days, p = 0.002) and full grip achievement (42.46 versus 32.70 days, p = 0.002) were also faster in the treatment group. Conclusions: The steroid-mannitol combination treatment for multiple metacarpal bone fracture patients in the acute postoperative phase promoted the reduction of hand edema and pain, leading to the earlier initiation of physical therapy, rapid improvement in joint motion, and faster achievement of full grip.

Chimeric flap pedicled with superficial branch of superficial iliac circumflex artery in repair of soft tissue defects of dorsal hand and metacarpal bone / 中华显微外科杂志

Objective:To investigate the effect of chimeric flap pedicled with superficial branch of superficial iliac circumflex artery in repair of soft tissue defect of dorsal hand combined with metacarpal bone defect.Methods:From May 2015 to January 2022, 34 patients(28 males and 6 females) of soft tissue defects of dorsal hand with metacarpal bone defects were treated in the Department of Orthopedics of Yibin Third People's Hospital. The age of patients ranged from 22 to 51 years old, with an average age of 37 years old. The areas of soft tissue defects after debridement were 2.5 cm×5.0 cm-4.5 cm×9.0 cm, and the defects were all in dorsal hand and dorsal wrist. The lengths of metacarpal bone defect were 1.8-4.1 cm. All the patients had only single metacarpal bone defect, among which: 14 patients had defects in first metacarpal bone, 7 in second metacarpal bone, 4 in third metacarpal bone, 8 in fourth metacarpal bone and 1 in fifth metacarpal bone. All the patients were repaired by chimeric flap pedicled with superficial branch of superficial iliac circumflex artery. The size of flaps were 3.6 cm×5.4 cm-5.2 cm×9.5 cm. Anticoagulation, thermal preservation and plaster fixation were applied for 4-6 weeks after surgery. Postoperative follow-ups included regularly outpatient clinic visit, telephone or Wechat reviews. Follow-up items covered: the feeling and appearance of flaps in recipient sites, healing of the donor sites and recovery of hand functions.Results:All the 34 chimeric flaps survived. Regular follow-up lasted for 3 to 15(average, 10) months. All incisions in the donor sites of hip healed in stage I. TPD of the flaps was 5.1-7.3(mean, 6.4) mm. Appearance of flaps in the receiving area were satisfactory without swelling. Movement of wrists and metacarpophalangeal joints met the basic requirement of movement. The healing time of metacarpal defect was 2-3 months with an average of 2.8 months. Hand functions were evaluated at excellent in 6 patients and good in 28, according to the Evaluation Standard of Upper Limb Partial Functional of Hand Surgery of Chinese Medical Association.Conclusion:The chimeric flap pedicled with superficial branch of superficial iliac circumflex artery is an ideal flap to repair the soft tissue defect in dorsal hand combined with metacarpal bone defect. It has advantages of less donor site damage, good blood supply of flap, simple surgical procedure, and one-stage repair of a combined soft tissue and metacarpal bone defects.

Human thumb consists of three phalanges and lacks metacarpal? A morphometric study on the long bones of the hand.

PURPOSE: For many years, it was thought that the thumb consists of just two phalanges that differentiate it from the other four medial triphalangeal fingers. But there are some old reports that few former scientists believed the thumb has three phalanges and it lacked a metacarpal, and the thumb metacarpal is a phalanx. So this anthropometric study was carried out by investigating the morphology of the long bones of the hand and correlations between the thumb metacarpal and other miniature long bones of the hand. METHODS: We studied anterior-posterior X-ray images of the right hands of 80 individuals from 18 to 65 years old. The exploration targets were the length of all metacarpals (MC), proximal phalanges (PP), middle phalanges (MP), and distal phalanges (DP). Friedman Repeated Measures Analysis of Variance and Dunn's post hoc test were carried out to compare the means of all variables. The correlation between all quantitative factors was done by Spearman Rank Correlation (Spearman's Rho) coefficient. RESULTS: Our results showed that the length of the phalanges and the total length of the fingers are independent of the related metacarpal length (P < 0.001). Also, the thumb metacarpal length in comparison to all bones of the hand was significantly different from all long bones of the hand except the proximal phalanx of the middle finger (P = 1). CONCLUSION: Based on the morphology of the long bones of the hand and the high similarity between the thumb metacarpal and phalanges especially the proximal phalanx of the middle finger, it can be suggested that the current thumb metacarpal is a proximal phalanx of the thumb.

Late Presentation of Palmar Dislocation of the Fifth Metacarpal Bone: Review of the Literature, Treatment Algorithm, and Case Report.

Introduction: Isolated palmar carpometacarpal dislocation of the small finger is infrequent, this injury often goes unnoticed in the evaluation at the emergency room, for which physical evaluation and X-ray findings can avoid missing this diagnosis. We describe a case report and propose a treatment algorithm for isolated dislocations of the carpometacarpal joint of the fifth finger to the palmar that is not diagnosed and treated early, using this algorithm, the surgeon will have a vision of the probable best treatment option. Case Presentation: A 50-year-old with late presentation of palmar dislocation of the fifth metacarpal bone, the diagnosis that went unnoticed in the initial emergency assessment. The patient was taken to an open reduction and internal fixation with an internal brace fixed at the base of the fifth metacarpal, the base of the fourth metacarpal and the hamate, and the fifth metacarpal was fixed to the fourth metacarpal with a Kirschner wire placed transversely to the axis of the metacarpal. Conclusion: Physical evaluation and X-ray findings, physicians can avoid missing isolated palmar carpometacarpal dislocation of the small finger. Using this algorithm according to the temporality of the injury, direction of the dislocation, and stability of the joint, the surgeon will have a vision of the probable best treatment option.

Stress fracture of the palmar, distal cortex of the third metacarpal bone: A diagnostic challenge with a good prognosis.

BACKGROUND: Transverse stress fracture of the palmar cortex of the distal aspect of the third metacarpal bone (TSF PCD McIII) is poorly documented. OBJECTIVES: To describe the typical signalment of this injury, the common clinical and radiological signs and prognosis. STUDY DESIGN: A retrospective hospital-based case series with follow-up of racing records. METHODS: All cases of TSF PCD McIII diagnosed among racehorses in training at the Hong Kong Jockey Club between 2011 and 2019 were identified. Clinical records were reviewed and documented signs were recorded for each case. Findings from a predefined list of radiological features were listed. Descriptive statistics were used to describe the age and training profile of horses, the clinical and radiological findings and time to return to ridden exercise. RESULTS: Twenty-three cases (n = 23) were identified. The majority (57%) had recently started or returned to training from a break and 35% (n = 8) of cases had not yet undertaken timed gallops at the time of injury. Most cases (20/23; 87%) were lame; in nine (39%), lameness was severe. Localised swelling of superficial soft tissues was reported in 15/23 (65%) cases. Pain on palpation of the distal McIII was present in 15/23 (65%) cases and in response to fetlock flexion in 12/23 (52%). Diffuse, localised increase in radiopacity, disruption to the outline of the bone periosteal surface and outward displacement of the button of the splint bone were common radiological features in early cases (70%, 67% and 67% of all cases). Sixty-one per cent of cases (14/23) were initially misdiagnosed. Most horses (n = 18/23) resumed training and racing after a median of 83 and 246 days. MAIN LIMITATIONS: Clinical notes were not consistent between cases. Radiographs were taken at different times. CONCLUSIONS: Horses commencing training are at risk of TSF PCD McIII, which presents with confusing clinical signs and subtle radiological findings. The long-term outlook is favourable.

Imaging and Gross Pathological Appearance of Changes in the Parasagittal Grooves of Thoroughbred Racehorses.

(1) Background: Parasagittal groove (PSG) changes are often present on advanced imaging of racing Thoroughbred fetlocks and have been suggested to indicate increased fracture risk. Currently, there is limited evidence differentiating the imaging appearance of prodromal changes in horses at risk of fracture from horses with normal adaptive modelling in response to galloping. This study aims to investigate imaging and gross PSG findings in racing Thoroughbreds and the comparative utility of different imaging modalities to detect PSG changes. (2) Methods: Cadaver limbs were collected from twenty deceased racing/training Thoroughbreds. All fetlocks of each horse were examined with radiography, low-field magnetic resonance imaging (MRI), computed tomography (CT), contrast arthrography and gross pathology. (3) Results: Horses with fetlock fracture were more likely to have lateromedial PSG sclerosis asymmetry and/or lateral PSG lysis. PSG lysis was not readily detected using MRI. PSG subchondral bone defects were difficult to differentiate from cartilage defects on MRI and were not associated with fractures. The clinical relevance of PSG STIR hyperintensity remains unclear. Overall, radiography was poor for detecting PSG changes. (4) Conclusions: Some PSG changes in Thoroughbred racehorses are common; however, certain findings are more prevalent in horses with fractures, possibly indicating microdamage accumulation. Bilateral advanced imaging is recommended in racehorses with suspected fetlock pathology.

A rare dislocation: an open isolated palmar dislocation of the head of the fifth metacarpal bone without fracture.

We present an open and isolated palmar dislocation of the head of the fifth metacarpal bone without fracture. The diagnosis, which was initially made based on the X-rays, was confirmed during the operation. The patient was satisfactorily treated with open reduction, Kirschner wires fixation and casting followed with hand physiotherapy.

Diagnosis and treatment of a closed and inverted metacarpal head fracture.

This case report documents a rare inversion of a closed metacarpal head fracture in the setting of polytrauma. Although rare, hemispherical articular bones can fracture and rotate 180°. Because of the symmetry of the bone and the rarity of an inverted, metacarpal head fracture, a delay in diagnosis and subsequent treatment can occur, which can lead to a poor outcome. This is particularly true in the setting of polytrauma. A 38-year-old male, polytrauma patient presented to the emergency department (ED) after falling off a bridge and being struck by an oncoming vehicle. He presented with multiple surgical fractures of the upper and lower extremities as well as his pelvis. Three days after he was brought to the ED, x-rays were performed of his painful left hand, which revealed an extra-articular third metacarpal head fracture, for which he underwent open reduction of the closed fracture. Both collateral ligaments were intact and the head fragment had inverted within the constraints of these ligaments. Some of the ligament and capsular tissue remained attached to the head fragment along the radial and ulnar margins but was otherwise entirely covered with cartilage. The reduction maneuver was difficult but after the reduction was achieved, the fracture appeared stable and no internal fixation was used. Post reduction, the injury was splinted for 2 weeks and then early motion was allowed. The fracture has since healed, and the patient has attained near-full function of the finger and joint.

Intracortical chondroma of the metacarpal bone: A case report.

BACKGROUND: Intracortical chondroma of the metacarpal bone which could be painful is an extremely rare condition and previously only one case has been reported. Due to the similar physical features and appearance on clinical imaging, it is difficult to differentiate between intracortical chondroma and osteoid osteoma. Therefore, pathological examination is usually required to establish a definite diagnosis, which is often carried out only after tumor removal. In this study, we describe a case of intracortical chondroma which developed in the metacarpal bone and demonstrate the utility of magnetic resonance imaging (MRI). CASE SUMMARY: We present a case of a 40-year-old man with intracortical chondroma of the metacarpal bone who was strongly suspected of having a tumor, and it was confirmed using contrast-enhanced MRI and successfully treated with curettage. MRI performed before tumor removal revealed signal intensity similar to that of the nidus of an osteoid osteoma. However, no abnormal intensity was observed in the bone or soft tissues surrounding the tumor. Such abnormalities on images would indicate the presence of soft-tissue inflammation, which are characteristics of osteoid osteoma. Furthermore, contrast-enhanced imaging revealed no increased enhancement of the areas surrounding the tumor. This is the first report to describe the contrast-enhanced MRI features of intracortical chondroma. This may serve as a guide for clinicians when intracortical chondroma is suspected. CONCLUSION: The contrast-enhanced MRI was useful for the differential diagnosis of intracortical chondroma.

How does bone strain vary between the third metacarpal and the proximal phalangeal bones of the equine distal limb?

Strain parameters at injury prone sites of the equine third metacarpal (MC3) and proximal phalangeal (P1) bones were investigated with the aim of improving understanding of injury pathogenesis. We hypothesized that dorsal principal and shear strain patterns, magnitudes and directions would differ from proximal-to-distal; and would be similar from medial-to-lateral across each bone. Unilateral limbs from nine equine cadavers were instrumented with rosette strain gauges during limb loading to 10,500 N. Gauges were attached at seven dorsal sites: middle MC3, distal MC3 (medial, middle, lateral) and proximal P1 (medial, middle, lateral). Outcome measures were analysed with repeated measures analysis of variance. Distal MC3 had the greatest, and proximal P1 the smallest magnitude of minimum principal and shear strains. Directions of maximum and minimum principal strain were similar at the middle and distal MC3 sites with a 20-40° direction difference compared to proximal P1. The patterns of strain magnitude and direction were similar from medial-to-lateral on distal MC3 but varied in pattern and magnitude among the P1 sites. Overall, as load reached maximum, direction of minimum principal strain became more axial in orientation, converging from opposite directions between bones, potentially maximising stability of the distal limb. The difference in strain parameters and strain ratio for adjacent anatomic sites on distal MC3 and proximal P1 was not anticipated, in light of the anatomic congruity of the metacarpophalangeal joint. Based on the predominance of shear strain across proximal P1, shear forces are likely the predominant biomechanical contributor to sagittal fractures of P1.

Antegrade intramedullary nailing in comminuted, open metacarpal bone fracture: maintenance of the length.

PURPOSE: The purpose of this study was to evaluate the radiological and clinical outcomes of treatment of comminuted open fractures of the metacarpal bone (MCB) with associated injuries to soft tissues, tendons, and neurovascular structures using antegrade intramedullary nailing (AIN) at least 2 years postoperatively. METHODS: Between January 2008 and December 2017, a total of 27 patients who met the inclusion/exclusion criteria were included in this study. The inclusion criterion was open and comminuted fracture (with/without segmental bone defects). We evaluated simple radiograph and computed tomography (CT) findings and clinical conditions (visual analog scale [VAS] pain score and Disabilities of the Arm, Shoulder, and Hand [DASH] score), including active range of motion (ROM) at metacarpophalangeal joint (MP) and grip strength at final follow-up. RESULTS: The mean preoperative angulation was 29.63° ± 7.59° and the mean shortening was 9.30 ± 2.38 mm. Union was achieved at mean 12.3 weeks postoperatively, without any complications due to operative treatment. The dorsal angulation measured on the CT scans, shortening on simple radiographs was significantly improved (10.26 °± 3.19°, 0.52 ± 1.05 mm, respectively). The final VAS and DASH scores were 0.41 ± 0.64 and 3.6 ± 2.47, respectively, indicating satisfactory outcomes. The final ROM was 85.0° ± 3.67°. The mean final grip strength was 89.56 ± 5.69% relative to the normal side. A mean extension lag at the MP joint of 12° was noted in three patients; however, it was resolved by additional tenolysis. CONCLUSIONS: AIN is a simple method for fixation of open comminuted metacarpal fractures accompanied by soft tissue injury. The simplicity of the method is beneficial for repairing associated injured structures and healing soft tissue. Minimized additional damage around the MCB during surgery and good stability resulted in satisfactory bony union with minimal angulation, shortening, and rotation. LEVEL OF EVIDENCE: Level IV, Retrospective case series.

A vascularized bone graft harvested from the dorsal base of the third metacarpal bone for the treatment of scaphoid nonunion.

The purpose of this retrospective study was to introduce the use of an alternative vascularized bone graft for treating scaphoid non-union. The vascularized bone graft was harvested from the dorsal base of the third metacarpal bone. From May 2014 to September 2017, 29 patients with scaphoid non-union were treated. Grip and pinch strengths were compared to the contralateral side. The patients rated wrist joint pain on a visual analogue scale. Wrist function was assessed on Mayo Wrist Score. p < 0.05 was considered statistically significant. 18 scaphoids healed at 6 weeks and the other 11 at 16 weeks. Follow-up ranged from 28 to 73 months, for a mean 48 months. At final follow-up, mean wrist flexion had improved from 65° (range, 51°-81°) preoperatively to 72° (range, 61-78°) (p > 0.05), for a contralateral value of 74° (range, 65°-86°). Mean extension had improved from 56° (range, 44°-72°) to 60° (range, 47°-76°) (p > 0.05) for a contralateral value of 66° (range, 52°-80°). Mean wrist pain improved from 4 (range, 3-8) to 2 (range, 0-4) (p < 0.05). Mean pinch strength improved from 6.4 kg (range, 5.2-7.3 kg) to 8.6 kg (6.1-9.9 kg) (p < 0.05). Mayo Wrist Score improved from 49 (range, 10-65) to 92 (range, 70-100) (p < 0.05). Transferring a vascularized bone graft harvested from the base of the third metacarpal bone was an effective alternative for the treatment of scaphoid non-union, achieving bone healing and normal wrist function without significant donor-site morbidity. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Is quantitative ultrasound a measure for metabolic bone disease in preterm-born infants? A prospective subcohort study.

In this study, we aimed to (a) evaluate postnatal changes in bone development in relation to growth and (b) to determine factors associated with bone development, from birth to 24 months of corrected age. The metacarpal speed of sound (mcSOS) and metacarpal bone transmission time (mcBTT) were used to evaluate bone development in 98 preterm infants, during hospitalization and follow-up. The mcSOS and mcBTT values not only declined in the first 6 weeks of hospitalization but also during follow-up. The mcSOS reached its lowest point at 12 months (ß=-34.64), while the mcBTT reached a plateau between 12 and 24 months (ß=0.06). Univariable analysis showed that gender (p=0.28), time (p<0.001), and growth parameters (p<0.001) were significant negative associated factors with mcSOS, whereas with mcBTT, time (p=0.009), length (p=0.063), length standard deviation scores (SDS) (p=0.027), head circumference (p=0.005), and head circumference SDS (p=0.007) were significant positive. The multivariable model revealed that time (ß= -3.364, p=<0.001), weight (ß=-0.007, p<0.001) and length (ß=1.163, p<0.001) for mcSOS and length (ß=-0.021, p<0.001), and length SDS (ß= 0.066, p<0.001) and head circumference (ß=0.049, p<0.001) for mcBTT remained highly significant associated factors.Conclusion: The most important finding is that mcSOS decreased and the mcBTT reached a plateau to 24 months. In both mcSOS and mcBTT, the growth parameters were significant factors.Clinical Trial Registration: N/A What is known: • Metabolic bone disease is one of the possible long term adverse outcomes after preterm birth. • Metacarpal speed of sound (mcSOS) and metacarpal bone transmission time (mcBTT) decline in the early postnatal period. What is new: • During follow-up, mcSOS further decreased and reached its lowest point at 12 months, while the mcBTT reached a plateau up to 24 months. • Postnatal nutrition in relation to comorbidity does not meet the optimal mineralization rate of the developing preterm bone.