Stressed or fractured: MRI differentiating indicators of physeal injury.

OBJECTIVE: To identify MRI findings that can indicate chronic physeal stress injury and differentiate it from acute Salter-Harris (SH) fracture of the pediatric knee or wrist. METHODS: IRB-approved retrospective study of consecutively selected knee and wrist MRIs from 32 athletes with chronic physeal stress injury and 30 children with acute SH fracture. MRI characteristics (physeal patency, physeal thickening, physeal signal intensity (SI), continuity of the zone of provisional calcification (ZPC), integrity of the periosteum and/or perichondrium, pattern of periphyseal and soft tissue edema signal, and joint effusion) were compared. RESULTS: Forty-eight chronic physeal stress injuries (mean age 13.1 years [8.2-17.5 years]) and 35 SH fractures (mean age 13.3 years [5.1-16.0 years]) were included. Any physeal thickening was more common with chronic stress injury (98% vs 77%, p = 0.003). Abnormal physeal SI was more common with SH fractures (91% vs 67%, p = 0.008). ZPC discontinuity strongly suggested chronic stress injury (79% vs 49%, p < 0.004). Periosteal and/or perichondrial elevation or rupture and soft tissue edema characterized most of the acute SH fractures (p < 0.001) and were seen only in 1 chronic stress injury (< 2%). While periphyseal edema was not significantly different in the two groups (p = 0.890), a joint effusion was associated with acute SH fracture (p < 0.001). CONCLUSION: Chronic physeal stress injury of the pediatric knee and wrist shows higher incidence of ZPC discontinuity and focal physeal thickening compared to SH fracture, reflecting disruption in normal endochondral ossification. However, these findings can overlap in the 2 groups. Periosteal and/or perichondrial injury, soft tissue edema signal, and joint effusion strongly suggest SH fracture and are rarely present with chronic stress injury.

Youth soccer players: patterns of injury involving the primary growth plates of epiphyses.

Youth soccer (football) is immensely popular internationally. Earlier participation, sport sub-specialization, and year-around practice have led to an increased incidence of injury from both acute trauma and repetitive overuse. The growth plates (physes) of the immature skeleton are particularly vulnerable to injury and delayed diagnosis can lead to future growth disturbance and long-term morbidity. Familiarity with the various components of the growth plate complex necessary for ensuring normal endochondral ossification is fundamental in understanding the various patterns of imaging findings following injury. This review discusses the zonal columnar arrangement of the growth plate proper and the contrasting function of the vasculature within the subjacent epiphysis and metaphysis. This is followed by an evidence-based discussion of the common patterns of injury involving the epiphyseal primary growth plate observed among youth soccer players: subcategorized into physeal fractures (direct injury) and physeal stress injuries (indirect insult to subjacent metaphysis). In this section, the role of imaging and characteristic imaging features will be discussed. While the normal physiologic and pathophysiologic mechanisms can be applied to other growth plates, such as primary growth plates underlying the apophyses and secondary growth plates surrounding the secondary ossificiation centers, which also undergo endochondral ossification, the current review is focused on injuries involving the primary growth plates underlying epiphyses.

Long-Term Clinical Outcomes Following Nonsurgical Management of Salter-Harris Type II Fractures of the Proximal Phalanx of the Small Finger: A Prospective Cohort Study.

PURPOSE: Juxta-physeal fractures at the base of the proximal phalanx (FBPP) of the small finger are one of the most common hand fractures in children. Although many of these fractures are treated nonsurgically, it is unclear which fractures benefit from surgery or the degree of acceptable angulation appropriate for nonsurgical management. Our study aimed to assess long-term, patient-reported outcomes regarding function, appearance, and pain after nonsurgical management of FBPP of the small finger in a pediatric population. METHODS: Our hospital Picture Archiving and Communication Systems database was queried to identify radiographs of the small finger of children between the ages of 8 and 16 years old taken from 2011 to 2021. Displacement on initial injury radiographs was calculated using the diaphyseal-metacarpal head angle. Patient-reported function, appearance, and pain were measured using standardized assessment tools sent to patients and parents electronically. Optional clinical photographs were uploaded by parents and assessed for residual clinical deformity. RESULTS: One hundred eighty-one eligible subjects were identified. Eighty (44%) agreed to participate, and 40 (22%) parent and 38 patient surveys were completed. The mean age at the time of injury was 11 years old (8-14 years), and the mean age at the time of survey completion was 17 years old (11-23 years). Patient T-scores were higher than the average reference T-score on the Patient-Reported Outcomes Measurement Information System Short Form v2.0-Upper Extremity. Overall, greater than 78% of patients and parents reported appearance as 8/10 or above on a VAS. Ninety-five percent (108/114) of patients reported no pain (0/10) for pain during activities and at rest. CONCLUSIONS: Children with up to 26° of initial coronal plane angulation reported better function than a reference population, good appearance, and no pain, at a mean of 6 years after injury. Our findings support nonsurgical management of most FBPP of the small finger in children. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Pediatric foot fractures on radiographs: distribution and predictors of surgery.

PURPOSE: To examine the distribution and characteristics of pediatric foot fractures on radiographs with respect to age and skeletal maturation, and to identify predictors of surgery. METHODS: This retrospective study included children (≤ 18 years) with foot fractures, who underwent radiographic examinations (2020-2022). Electronic medical records were reviewed to obtain demographic and clinical data. Fracture characteristics, including anatomic location, presence of displacement, angulation, articular involvement, and, if skeletally immature, physeal involvement and Salter-Harris fracture pattern were collected. Logistic regression models were used to identify predictors of surgery. RESULTS: 1,090 (596-boys, 494-girls; mean age, 11.0 ± 4.0 years) patients with 1,325 (59.8% metatarsal, 33.8% phalangeal, and 6.4% tarsal) fractures were included. Fractures of 1st metatarsal were more common among younger children whereas fractures of 2nd-4th and 5th metatarsals were more common among older children (median ages: 5.9 years vs. 10.3 years and 12.4 years, p < 0.001). Intra-articular fractures were more common among maturing and mature than immature bones (25.3% and 20.4% vs. 9.9%, p < 0.001). Physeal involvement was uncommon (162/977, 16.6%) and the most common pattern was Salter-Harris type II (133/162, 82.1%). A minority (47/1090, 4.3%) of patients required surgery and independent predictors of surgery included physeal involvement (OR = 5.12, 95% CI: 2.48-10.39, p < 0.001), multiple fractures (OR = 3.85, 95% CI: 1.67-8.53, p = 0.001), fracture displacement (OR = 9.16, 95% CI:4.43-19.07, p < 0.001), and articular involvement (OR = 2.72, 95% CI:1.27-5.72, p = 0.008). Using these predictors, the likelihood for surgery ranged between 8.0% with 1 and 86.7% with 3 predictors. CONCLUSION: Pediatric foot fracture patterns differed based on age and regional skeletal maturation. Physeal involvement, multiple fractures, fracture displacement, and articular involvement were independent predictors of surgery in our study group.

MRI findings of growth plate fractures of the knee: are there age- and fracture-dependent differences?

OBJECTIVE: To investigate MRI findings in children with physeal fractures of the knee with respect to age, location, and articular involvement. METHODS: Children with physeal fractures who underwent knee MRI between 2008 and 2021 were included. Two radiologists retrospectively reviewed all examinations to determine articular involvement, findings of physeal instability (perichondral disruption, periosteal entrapment), and internal derangement (cruciate ligament injury, meniscal tear, chondromalacia). Independent samples t, Mann-Whitney U, Pearson's chi-square, and Fisher's exact tests were used to compare findings. RESULTS: Fifty-six patients (37 boys, 19 girls; mean age: 12.2 ± 2.5 years; 32 distal femur, 24 proximal tibial fractures) included 24(43%) intraarticular fractures. Fractures were more common in the tibia than the femur (67% versus 25%, p = 0.004) and intraarticular fractures were more common in older than younger children (13.1 ± 2.0 versus 11.5 ± 2.7 years, p = 0.01), to associate with chondromalacia (46% versus 12%, p = 0.02) and undergo surgery (33% versus 10%, p = 0.04) when compared to extraarticular fractures. Perichondral disruption (n = 44, 79%) and periosteal entrapment (n = 13, 23%) did not significantly differ based on location or articular involvement (p > 0.05). At a median follow-up of 17.5 months (interquartile range: 1.25-34), 3 patients (2 intraarticular, 1 extraarticular fractures) developed osteoarthritis, osteochondral lesion, and leg-length discrepancy from growth arrest, which required additional surgery. CONCLUSION: Intraarticular physeal fractures were more common with older children, associate with chondromalacia, and underdo surgical intervention when compared to extraarticular fractures of the knee. While MRI findings of physeal instability were common, no significant differences were found between fractures based on anatomic location or fracture pattern.

Maturation-dependent patterns of knee injuries among symptomatic pediatric soccer players on MRI.

OBJECTIVE: To systematically investigate the prevalence of knee MRI findings among symptomatic pediatric soccer players with respect to skeletal maturity and to identify predictors of surgery. METHODS: This IRB-approved, HIPAA-compliant retrospective study included soccer players (< 18 years of age) who underwent MRI examinations in the past 5 years (2018-2023). Two radiologists retrospectively and independently reviewed all examinations to categorize skeletal maturity and to identify osseous and soft tissue findings. Findings were compared between maturation groups, and logistic regression models were used to identify predictors of surgery. RESULTS: Ninety-seven players (45 boys, 52 girls) included 39 skeletally immature, 21 maturing, and 37 mature knees. Kappa coefficient for interobserver reliability ranged between 0.65 and 1.00. Osgood-Schlatter disease (OSD) was more common among immature than maturing and mature knees (25% vs 14% and 5%, p = 0.04); anterior cruciate ligament (ACL) injury was more common among maturing and mature than immature knees (59% and 48%, vs 15%, p < 0.01); and meniscal tears were more common among mature than immature and maturing knees (medial, 41% vs 18% and 14%, p = 0.03; lateral, 43% vs 21% and 19%, p = 0.04). Players in the mature group were more likely to undergo surgery (p = 0.01). The presence of an effusion (OR = 19.5, 95% CI 2.8-240.9, p = 0.01), ACL injury (OR = 170.0, 95% CI 1.3-6996.9, p < 0.01), and lateral meniscal tears (OR = 10.8, 95% CI 1.8-106.1, p = 0.02) were independent predictors of surgery. CONCLUSION: Differential patterns of injury were found among symptomatic pediatric soccer players; the presence of an effusion, ACL injury, and lateral meniscal tears were independent predictors of surgery, likely contributing to the higher rates of surgery among skeletally mature players.

Distribution of pediatric hand fractures: age- and bone maturation-dependent differences.

PURPOSE: To investigate the distribution and characteristics of fractures of bones of the hand on radiographs with respect to age and skeletal maturity of the fractured bone, and to identify predictors of surgery. METHODS: This cross-sectional, retrospective study included children (≤ 18 years) with hand fractures who underwent radiographic examinations (2019-2021). Fracture location, presence of displacement (≥ 2 mm), angulation (≥ 10°), articular extension, and if skeletally immature, then physeal involvement and Salter-Harris grade were recorded. Mann-Whitney U, Kruskal-Wallis, Fisher's exact, and chi-square tests as well as logistic regression analyses were used. RESULTS: Study group of 508 (350 boys, 158 girls; median age, 11.9 years) included 575 (63% phalangeal, 37% metacarpal, and 0.3% carpal) fractures. Younger children were more likely to sustain phalangeal and older children carpal and metacarpal fractures (median ages: 10.8 vs 12.3 and 13.8 years, p < 0.001); and fractures of the small finger accounted for 50% of metacarpal and 43% of phalangeal fractures. Fracture displacement (12% vs 22%, p = 0.02) and angulation (25% vs 49%, p < 0.001) were more common with mature than immature bones. A third of immature bones had physeal involvement and the most common pattern was Salter-Harris type II (89%). Surgical intervention was uncommon (11%) and independent predictors were displacement (OR = 3.99, 95% CI 1.95-8.19, p < 0.001) and articular extension (OR = 5.11, 95% CI 2.00-13.07, p < 0.001). CONCLUSION: While younger children were more likely to sustain phalangeal than metacarpal fractures and less likely to have displacement and angulation when compared to older children; only displacement and articular extension were significant independent predictors of surgery.

Surgical repair of Salter-Harris type II fracture of the distal humerus: short and long-term outcomes in a case series of three dogs and one cat.

CASE HISTORIES: Three dogs and one cat sustained forelimb trauma and were presented to a university veterinary clinic (Liège, Belgium) and a private veterinary hospital (Beacouzé, France). All four animals were referred for surgery. CLINICAL FINDINGS: Two dogs and the cat were ambulatory on admission but unable to bear weight on the affected limb. One dog was non-ambulatory and lacked voluntary movement and sensation in one forelimb. Salter-Harris type II fractures of the distal humerus were diagnosed by radiography in all cases; avulsion of the brachial plexus and pelvic fractures were also present in the non-ambulatory dog. TREATMENT AND OUTCOME: All Salter-Harris type II fractures were stabilised by open reduction and internal fixation with cross pins. One minor complication (seroma) and three major complications (implant migration) developed after surgery. The pins were completely removed in one case and partially removed in two cases to resolve these complications. At the final follow-up examination (12-31 months after surgery), owners reported no lameness in three of the four cases and grade 2/5 left forelimb lameness in one case. CLINICAL RELEVANCE: This type of fracture is rarely described in the literature; however, it should be included in the differential diagnoses of traumatic humeral fractures in growing dogs and cats. In this case series, we achieved fair-to-excellent short-term and long-term outcomes after osteosynthesis of Salter-Harris type II fractures by cross pinning.

SalterHarris fractures in paediatric skiers and snowboarders.

The incidence of paediatric fractures among winter sport athletes is not adequately studied. Our objective was to categorize fractures that occurred in paediatric skiers and snowboarders at a single ski resort. X-rays of 756 skiers/snowboarders aged 3-17 diagnosed with a fracture were categorized using the Salter-Harris (SH) classification. SH fractures were seen in 158 (21%) patients, with 123 (77%) being Type II. There were no significant differences between patients with a SH fracture and patients with a non-SH fracture for age, sex, snowboarding or skiing, mechanism of injury, terrain or the resort conditions on the day of injury. The most common mechanism of injury was falling onto snow while collisions resulted in more severe injuries. Compared to fractures without growth plate involvement, a higher proportion of SH fractures were seen in the humerus, radius, fibula and thumb; a lower proportion of SH fractures were observed at the tibia and clavicle.

Surgical management of a Salter-Harris type I proximal physeal fracture of the tibia in a foal: a case report.

BACKGROUND: One of the traumatic fractures occurring in the hindlimb of the foals is physeal fractures of the tibia. The most common type of proximal tibial fracture in foals is reported to be Salter-Harris type II. CASE PRESENTATION: This case report describes the history, clinical signs, radiographic findings, and surgical management of a proximal physeal fracture of the tibia due to the kick trauma in a 2-weeks-old Kurdish female foal, with signs of left pelvic limb lameness, valgus deviation with non-weight-bearing, non-mobility in stifle region and crepitation in the affected area. In this case, radiography was utilized to confirm the fracture and detect the exact location of the fracture fragments. The Salter-Harris type I accompanied by tibial tuberosity fracture was diagnosed. In this case, a size 4.5 mm seven-hole, T-plate, and cortical bone screws were employed to fix the physeal fracture, and a cortical bone screw was utilized to fix the tibial tuberosity in the normal position. Case follow-up during two months showed no significant complications, and the patient was fully recovered (no lameness anymore). CONCLUSIONS: To our knowledge, this is the first report of Salter-Harris type I fracture in proximal tibia accompanied by tibial tuberosity fracture in a foal treated by a T-plate implant. A cortical screw in lag fashion for tibial tuberosity was utilized in this case for the first time, and the results were satisfying. T-Plate fixation can be recommended as an effective surgical treatment for proximal tibial fractures in foals.

Retrospective evaluation of surgical technique, complications and long-term outcome of lateral and medial humeral condylar fractures in 80 dogs.

CASE HISTORY: Medical records from a single veterinary teaching hospital in Giessen, Germany were retrospectively reviewed for dogs presenting with medial or lateral humeral condylar fractures (HCF) between 2007 and 2019. Data regarding surgical technique and complications were collected from the medical records. These were supplemented through information obtained from telephone interviews with referral veterinarians and from an owner questionnaire completed ≥12 months after surgical repair, which also provided data regarding the outcome. CLINICAL FINDINGS: Eighty dogs with 85 HCF were identified: 13 (15.3%) HCF were medial (bilateral in two dogs) and 72 (84.7%) were lateral (bilateral in three dogs). French Bulldogs (n = 19/80; 23.8%) were most commonly affected. Patients were predominantly skeletally immature and light-weight, with a median age at the time of presentation of 3 (min 2, max 118) months and with a median body weight of 6.4 (min 1, max 46) kg. There were 38 female (47.5%) and 42 male (52.5%) dogs. Fractures developed most frequently secondary to minor trauma (67/77; 87.0%). Dogs were presented in 35/84 (41.7%) cases more than 24 hours after fracture occurrence. TREATMENT AND OUTCOME: Surgical treatment was performed in 80/85 (94.1%) HCF. An open reduction and internal fixation approach was chosen in all cases. A transcondylar screw (TS) combined with a supracondylar (SC) K-wire (67/80; 83.8%) was the most frequently used fixation technique. Considering all fracture fixation methods, complications (26/80; 32.5%) were classed as minor in 10 (12.5%), major in 14 (17.5%) and catastrophic in two (2.5%) of the 80 surgically treated HCF. Long-term outcome was excellent in 68.6% (24/35 HCF) and very good in 22.9% (8/35 HCF) of the cases for which follow-up information was obtained. Additionally, owner information revealed that 85.7% of dogs (30/35 HCF) were free of lameness in the long-term. CLINICAL RELEVANCE: This case series demonstrates that surgical repair of lateral and medial HCF with a TS and SC K-wire is a viable option to consider in skeletally immature and light-weight patients. Complications occur frequently after surgical fixation of HCF, but owners can expect a very good to excellent long-term outcome in the majority of cases.

The physical examination is unreliable in determining the location of the distal fibular physis.

OBJECTIVES: Salter-Harris type 1 (SH1) fractures of the distal fibula are acute orthopedic injuries with tenderness over the physis without radiographic evidence of fracture. Our primary objective was to establish the accuracy of the physical examination performed by pediatric emergency medicine (PEM) physicians in determining the location of the distal fibular physis compared to a criterion standard of ultrasound. METHODS: This was a prospective, observational study at an urban academic pediatric emergency department of a convenience sample of children aged 4 to 10 years old between March 2019 and March 2020. A PEM physician or fellow examined the patient's distal fibula and marked the location of the physis with a marker. A study investigator scanned the distal fibula to establish the location of the physis on ultrasound and measured the distance between the clinician's estimated position and the actual sonographic position. We a priori defined a clinically accurate position as a distance of ≤5 mm. We compared the accuracy rate of physical examination to ultrasound landmarking using proportions with 95% confidence intervals (CI). RESULTS: We enrolled 71 patients, of whom 52 (73%) were male. The mean age was 6.7 years and the mean weight was 25.5 kg. Participating PEM physicians included 18 attending physicians and 2 fellows. The distal fibular physis was correctly identified in 24 patients, yielding an accuracy rate of 34% (95% CI 23%-46%). The mean distance between the physician's estimated position and the sonographic position was 7.4 mm (95% CI 6.4-8.4 mm). CONCLUSIONS: PEM physicians were unable to accurately identify the distal fibular physis on physical examination.

Clinical utility and economic impact of routine delayed follow-up radiographs in children with uncomplicated distal radius Salter-Harris 2 fractures.

BACKGROUND: Salter-Harris 2 fractures of the distal radius are common in pediatrics. Children with these fractures have a theoretical risk of developing a physeal bridge with subsequent growth disturbance. OBJECTIVE: The purpose of this study was to investigate the clinical utility and economic impact of obtaining routine delayed radiographs in asymptomatic patients with uncomplicated Salter-Harris 2 fractures of the distal radius. MATERIALS AND METHODS: Radiology records were searched retrospectively between Jan. 1, 2016, and Jan. 1, 2018, to identify patients with an acute Salter-Harris type 2 fracture of the distal radius and delayed wrist radiography 3 to 8 months after the injury. Exclusion criteria included distal radius surgery, clinical symptoms, secondary wrist trauma or a history of infection. The financial cost associated with follow-up imaging was determined based on standard charges associated with wrist/forearm radiography, wrist magnetic resonance imaging (MRI) and orthopedic clinical care. RESULTS: A total of 381 children with Salter-Harris 2 fractures of the distal radius and delayed radiographs were identified, 56% male (ages 1-18 years, mean: 9.8 years). Four children were excluded because of surgical intervention or clinical symptoms to the same wrist resulting in 377 subjects. There were five confirmed positive cases (1.3%) of distal radius physeal bridge formation, with four cases confirmed on MRI and one case confirmed clinically and radiographically. Based on routine institutional charges for the wrist/forearm radiographs and orthopedic clinic visits, the total billed charges for the 377 patients would equal $245,804, or $49,161 in billed charges per identified physeal bridge. Only three of the five positive cases of confirmed physeal bridge went on to surgical treatment. The billed charges per identified physeal bridge requiring surgery were $81,935. CONCLUSION: In asymptomatic children with uncomplicated Salter-Harris 2 fractures of the distal radius, detection of a physeal bridge on delayed radiographs is rare. The financial burden of routine delayed follow-up in asymptomatic patients, a common clinical practice, is an important consideration.

Should you fix again? An unusual fracture of a distal epiphyseal radius fracture - A case report.

Currently, Salter-Harris (SH) classification is generally used in physeal fractures, as it is reliable and valuable in many cases. Although this clasification system describes many different fracture configurations, still there is an unclassifed group of fractures. Here, we present the case of an 11-year-old boy who underwent surgery after fracture of distal radial epiphysis,of the type still unclassified according to SH classification. The main reason for ourresearch was that the line of treatment could not be decided initially after the first operation. The current classsifications that are close to SH and essentials on the neccesity of surgical approach were dicussed. Surgery must be attempted in cases in which it cannot be decided whether it is a SH type 2 or 3. Besides this situation, an attempt must be made for the classification of the fracture (Ogden tip 2b, Sferoupulos tip 3). Another important point is to decide where the fracture line goes in the layers of physis.

Correction of post traumatic tibial varus deviation with hexapodalic external fixator.

Physeal fractures are typical in childhood and for their involvement of the germinal layer of the physis they can be followed by growth complications. Axial deviation is one of these. Considering the young age of the patients it is critical to restore articular correct alignment with the least invasive surgery possible. We report here the first case of correction of post traumatic tibial varus deviation with exapodalic external fixator.

Pediatric ankle injuries: utilizing the Dias-Tachdjian classification.

Pediatric ankle injuries require timely diagnosis due to their involvement of the distal tibial physis and subsequent impact on long bone growth. These injuries occur in a predictable pattern based on ankle position, direction of force, and degree of closure of the distal tibial physis. The Dias-Tachdjian classification describes possible ankle injury patterns for the completely open physis, and we present a simplified algorithm for applying this system in routine radiographic interpretation. Similar to the Lauge-Hansen classification in adults, the Dias-Tachdjian system is based on the position of the foot and direction of force at the time of injury with four major patterns: supination-inversion, pronation-eversion external rotation, supination-plantar flexion, and supination-external rotation. In addition, we examine the effect that the closing distal tibial physis has on adolescent fracture patterns (specifically, Tillaux and triplane fractures). Awareness of these injury patterns helps the radiologist to identify nondisplaced fractures and subtle physeal injuries with implications for surgical and/or conservative management.

[Ankle fractures in children and adolescents]. / Sprunggelenkfrakturen im Kindes- und Jugendalter.

In children and adolescents, injuries of the ankle are seen frequently in routine practice. The fracture pattern is less dependent on the mechanism of injury than on the maturity of the growth plate. Therefore, a differentiation is made between fractures with open epiphyses and fractures with a closing growth plate in adolescents. The potential for growth-related spontaneous deformity correction is limited, so axial alignment especially in the frontal plane has to be achieved during initial treatment. In displaced articular fractures an anatomical reconstruction of the articular surface and stable osteosynthesis have to be achieved to minimize the risk of early osteoarthritis. Growth arrest is not always avoidable despite an ideal reconstruction and can occur in all fracture types; however, with optimal conservative or surgical treatment, iatrogenic damage of the epiphysis can be avoided thereby reducing the incidence of growth disorders as a complication of ankle fractures in children and growing adolescents.

A biomechanical comparison of Kirschner-wire fixation on fracture stability in Salter-Harris type I fractures of the proximal humeral physis in a porcine cadaveric model.

BACKGROUND: The physis is the weakest component of immature long bones, and physeal fractures constitute about 30% of fractures in growing dogs. Fractures of the proximal humeral physis typically have a Salter Harris type I or II configuration. These fractures require accurate reduction and adequate stabilization to allow for any potential continued longitudinal bone growth, in conjunction with physeal fracture healing. Conventional internal fixation of these fractures involves insertion of two parallel Kirschner wires, although other methods described include tension band wiring, Rush pinning, and lag screws. However these recommendations are based on anecdotal evidence, and information about the biomechanical stability of physeal fracture repair is sparse. The unique anatomical structure of the epiphyseal-metaphyseal complex makes the gripping of the epiphysis for ex vivo biomechanical testing of physeal fracture repair very challenging. The objective of our study was to biomechanically assess the optimal number (three, two or one) of implanted Kirschner wires in a porcine Salter Harris I proximal humeral physeal fracture model, using motion analysis tracking of peri-fragmental retro-reflective markers while constructs were subjected to a constant axial compression and a sinusoidal torque of +/- 2 Nm at 0.5 Hz for 250 cycles. RESULTS: There were significant differences between the three constructs (three, two or one Kirschner wire repair) for gross angular displacement (p < 0.001). The difference between three pins and two pins on toggle was not significant (p = 0.053), but both three-pin and two-pin fixation significantly reduced rotational toggle compared to one-pin fixation. Construct stiffness was not significantly different between any of the pin groups (p > 0.33). CONCLUSIONS: Motion analysis tracking using peri-fragmental markers in this porcine model of physeal fracture repair found that the stability at the fracture site of one-pin fixation was significantly less than two-pin and three-pin fixation. Whether there was increased stabilization of these fractures with three-pin fixation compared to two-pin fixation was not conclusive in this porcine model.

Epidemiology of proximal humeral fractures: a detailed survey of 711 patients in a metropolitan area.

BACKGROUND: Literature lacks data concerning several epidemiologic aspects of proximal humeral fractures (PHFs). METHODS: This retrospective study included 711 consecutive patients (209 men, 502 women) who sustained a PHF in the last 3 years. Participants were divided into 2 groups, adults and children. Data regarding age, sex, date, and fracture side were collected. According to the mechanism of injury, we arbitrarily distinguished 7 subgroups. PHFs were classified according to the head-greater-lesser-shaft (HGLS)-Hertel classification and to the Salter-Harris classification using x-ray and computed tomography imaging. RESULTS: PHFs represent 5.03% of the overall fractures. The right side was involved in 389 patients (54.7%; P = .6). The mean age of male and female patients was 55.4 (standard deviation, 21.9) years and 67.0 (standard deviation, 16.1) years, respectively (P = .0001). Significant differences in the trauma mechanism between female patients (street/home low-energy trauma) and male patients (high-energy trauma) were found. A significant correlation between trauma mechanisms from 1 to 5 and fracture patterns H-G-L-S, HL-G-S, HGL-S, and HLS-G was observed. The occurrence of the same patterns significantly varied according to different age subgroups. Considering the pediatric population, a significant incidence of Salter-Harris 2 in both genders was found. No correlation was observed between the fracture patterns and the trauma mechanism. CONCLUSIONS: PHFs have a higher prevalence and incidence in females and in older age, respectively; they are more frequent in the winter months. In addition, male fractures are due to different traumatic events than those in females. A correlation between trauma and PHF pattern was evident only for adults. Some fracture patterns are correlated with different ranges of age in all patients.

Distal femoral physeal crush injury with metaphyseal comminution - A report of two cases and a new perspective to physeal injury.

The physis of a long bone may get 'sandwiched' and crushed between the metaphysis and the epiphysis if it is traumatically loaded along its long axis. Such a physeal injury may lead to complications like angular deformities and growth restrictions and hence, management of such injuries requires adequate planning and attentive execution. Two patients with distal femoral physeal crush injury were treated using a ring fixator such that one ring had the wires passing through the epiphysis and the other through the femoral shaft. On table image intensifier controlled distraction of the crushed physis was done to bring the height of the physis similar to that of the opposite limb. Patients were followed up for more than two years clinically and radiologically. There was no clinical or radiological angular deformity of the operated limbs. MRI scans showed intact physes with no physeal bar formation in either of the two patients. The distraction obtained by the ring fixator appears to have provided ample 'breathing space' to the compressed physis and that the growth potential may have been re-gained by the procedure. However, two years is a relatively short duration of follow-up and further follow-up of longer duration and in greater number of patients is needed to gauge the actual effectiveness of the technique used by us.