Neonatal Birth Fractures

Abstract

Fractures in newborn infants due to trauma imparted by the birthing process are rare. These skeletal injuries can occur in the form of diaphyseal fractures or, much less commonly, separation of physes. Often, prompt recognition of birth fractures is difficult, which may lead to late presentation. Careful and thorough physical examination can identify the presence of these injuries, leading to appropriate treatment. Diaphyseal fractures can be treated non-operatively with light immobilization and comfort measures, with an excellent prognosis. Physeal injuries more often require surgical treatment to stabilize the displaced epiphyseal fragment after restoring anatomy. This review is designed for the orthopaedic clinician as an overview of the most commonly encountered varieties of these rare birth fractures so that they may be better equipped to recognize, diagnose, and offer appropriate treatment.

Key Concepts

• (1)Fractures and physeal separations sustained from birth trauma are rare and often require a high index of suspicion for diagnosis.
• (2)The overwhelming majority of diaphyseal fractures sustained from birth trauma can be treated nonoperatively with an excellent prognosis.
• (3)Physeal separations can be easily confused with other diagnoses, such as joint dislocations, and more often require surgical intervention for stabilization.

Introduction

Birth fractures are defined as those sustained from trauma due to the delivery process of the neonate. These injuries tend to occur at a rate of about 0.23 per 1000 live births [1], and can manifest as fractures to either the diaphysis or the physis. Despite advances in obstetric care and delivery techniques, birth fracture remains a pertinent concern and can be a source of great anxiety for the newly minted parent. The overwhelming majority of isolated fractures caused by the birthing process heal uneventfully without long-term consequences, but injuries to the physis or concomitant brachial plexus injuries may have more sinister sequelae. This article reviews the incidence, risk factors, and treatment for various fractures that can be sustained at birth.

Diaphyseal fractures

Clavicle fracture

Clavicle fractures are the most common type of birth fracture. Their incidence in the literature varies widely from around 0.05%–3.2% [[2], [3], [4], [5], [6], [7]]. Shoulder dystocia is a well-established risk factor for injury to the brachial plexus at delivery [8], and many previous studies and conventional wisdom have suggested an association of shoulder dystocia with neonatal clavicle fractures [[9], [10], [11], [12], [13], [14]]. However, other investigations have failed to identify this association [7,[15], [16], [17]]. Previous studies looking specifically at neonatal clavicle fractures have highlighted various risk factors, of which the most commonly identified include instrument-assisted delivery and macrosomia (birth weight >4,000 ​g) [4,[9], [10], [11], [12], [13], [14], [15], [16],18]. Although the majority occur in the setting of vaginal deliveries, they can still occur with cesarean sections as well [3,4]. Many studies have found a predominance of right-sided clavicle fractures compared to left [[2], [3], [4]]. This is thought to be because of the more common left occipital anterior position of delivery, leading to more pressure on the right shoulder and, thus, a higher chance of right-sided clavicle fracture.

Clinical diagnosis of clavicle fractures can often be difficult in the immediate postnatal period, leading to a noninsignificant frequency of missed injuries. Often, the diagnosis is made in a delayed fashion by a palpable callus when the child is seen in the outpatient setting a few weeks after birth (Fig. 1). Initial signs and symptoms may include irritability with movement of the affected arm, palpable crepitus, asymmetric swelling overlying the clavicle, or an asymmetric Moro reflex. However, many clavicle fractures may not cause obvious symptoms and may be clinically silent [2]. Plain radiography can confirm a suspected diagnosis (Fig. 2A) but may not be necessary in the asymptomatic infant with a palpable, stable callus. In the instance of a painless callus, the astute clinician will also remember what appears to be an old clavicle fracture may be congenital pseudarthrosis of the clavicle, which almost always is on the right side (Fig. 3A and B).

Figure 1.

AP radiograph showing a displaced clavicle fracture with robust callus formation in a 17-day-old male who presented due to a palpable bump that the parents noticed over the child's clavicle.

Figure 2.

A: AP radiograph of a newborn female with a displaced left clavicle shaft fracture. B: AP radiograph of the same patient at age 10 weeks. Note the clavicle has regained its anatomic shape and is remodeling nicely.

Figure 3.

Images courtesy of Ken Noonan, MD. A: Clinical appearance of a right congenital pseudarthrosis of the clavicle in a 4-year-old male. B: Radiographic appearance of the same patient. Note the blunted, sclerotic edges of the lateral and medial aspects of the clavicle.

Treatment of neonatal clavicle fractures is nonoperative. Infants with painful arm range of motion can be gently swathed with a soft bandage or have their sleeve pinned to their shirt, but often even immobilization is unneeded. The prognosis after these injuries is universally excellent, with full remodeling (Fig. 2B) and no functional deficits expected.

Humeral shaft fracture

The incidence of humerus fractures due to birth trauma varies from 0.01%–0.37% [1,5,19,20] of births in the literature. Risk factors include complicated labor, breech, preterm infancy, multiple births, shoulder dystocia, macrosomia, and instrument-assisted delivery [5,19,20]. However, there is a paucity of studies on humeral shaft fracture to define these risks, as most studies on birth injuries combine long bone fractures. A humeral fracture can occur in the setting of vaginal or cesarean delivery [1,20]. Interestingly, some studies have found a higher incidence in male infants [20], although the reasons for this are unknown. Clinical signs and symptoms to support the diagnosis include gross mobility at the fracture site, pain with arm movement, localized swelling, an asymmetric Moro reflex, and/or pseudoparalysis. This must be differentiated from true paralysis, which can be seen in brachial plexus birth palsy. Fractures are usually midshaft; the diagnosis can be confirmed with ultrasound or plain radiography [21].

These injuries are treated nonoperatively with gentle immobilization techniques, including swathing the infant with a soft bandage or safety-pinning the sleeve to the shirt. Perhaps no other injury exemplifies the power of remodeling in the immature skeleton than neonatal humerus fractures—fractures that initially unite with severe angulation exhibit remodeling to normal alignment with time (Fig. 4) [22]. The prognosis is excellent, with no expectation of long-term cosmetic or functional deficits.

Figure 4.

A, B: AP and lateral radiographs of an infant female on the day of birth with a displaced left humeral shaft fracture. C, D: AP and lateral radiographs of the same fracture two weeks later. Note the increased displacement and angulation, now with obvious callus formation. E, F: At age 15 months, the fracture has completely healed and remodeled to normal alignment.

Femoral shaft fracture

Birth-related femur fractures are seen in approximately 0.013%–0.089% of neonates [1,23,24]. Short oblique or spiral patterns of the midshaft or proximal shaft are typical of birth-related fracture patterns. Risk factors include breech presentation, multiple births (ie, twins, triplets, etc.), premature birth, small for gestational age [1,20,23,25], and underlying medical conditions affecting bone fragility. These fractures can occur with either vaginal or cesarean delivery, with some small case series showing the latter as a risk factor [1,[23], [24], [25]]. However, this could be a confounder for a more complicated birth (eg, breech leading to cesarean section). The diagnosis can be suspected with gross crepitus on palpation, pain with movement of the affected limb, or asymmetric swelling, and can be confirmed with radiographs (Fig. 5A–C) or ultrasonography. Often, swelling is the first hint that a femur fracture is present, leading to delayed diagnosis of a few days as the swelling develops into a noticeable difference [25].

Figure 5.

A: A diaphyseal short oblique femur fracture in a newborn girl. B: 1 month later, there is robust callus formation. C: At age 16 months, the healed fracture has fully remodeled.

Parents of neonates affected by a femur fracture can expect healing and excellent outcomes with a very low risk for angulation or limb length discrepancy long-term and no functional deficits, regardless of the treatment modality employed [1,[23], [24], [25], [26]]. Contemporary treatment includes casting (either toe to groin cast or spica cast) or a Pavlik harness. Some studies describe infants who have appropriately healed a missed femur fracture without treatment [23]. At our institution, we prefer treatment in a Pavlik harness over other options, as it avoids the parental headache of cast care, the potential skin issues of skin traction and/or casting, and seems to be the least hindering to early bonding with parents.

Physeal separations

Apart from fractures to the diaphyses of long bones, birth trauma can cause disruption and separation of the physes of long bones. These injuries are rare but are important to keep in mind when evaluating a newborn with suspected birth trauma to avoid a missed diagnosis. The humerus is the most commonly affected bone of these rare physeal injuries, and either the proximal [[27], [28], [29], [30], [31], [32], [33], [34]] or the distal [[35], [36], [37], [38], [39], [40], [41], [42]] physis can be involved. Injuries to the femoral physis are much less common, with a few case reports of distal femoral epiphyseal separation [[43], [44], [45], [46], [47], [48], [49], [50], [51]] and even fewer for the proximal femur [[52], [53], [54], [55]]. There are even described reports of separation of the tibial and fibular physes [50,56].

Physeal birth injuries can be seen with vaginal and cesarean section deliveries and are thought to result from difficult labor with shear or torsional forces to the limb. Pain, decreased motion at the extremity, localized swelling, and potential crepitus at the site of injury can all be seen with these injuries, but largely lack specificity. The diagnosis often remains elusive and can be easily missed, as plain radiography is often hard to interpret since secondary ossification centers in the epiphyses have often not yet erupted. Ultrasound and MRI can be diagnostic owing to their ability to “see” cartilage, but they also have drawbacks; ultrasound requires the availability of a skilled technician and radiologist, and MRI is expensive and likely requires the child to be sedated. Knowledge of these injuries is important, as the clinician evaluating the child in whom “something isn't right” with their limb must keep these rare entities on the differential. Many times, radiologists may miss the diagnosis without the added benefit of the clinical correlation bedside clinicians are privy to [35].

Distal humeral physeal separation

Distal humeral physeal separations are the most common type of physeal separations. However, it should be noted that due to the rarity of these types of injuries and the ease with which their diagnosis is typically missed, there are no consistent epidemiologic data upon which to draw solid incidence-related conclusions. Radiographically, it may appear as if the elbow is dislocated, as the radio-ulnar relationship is maintained but displaced relative to the humerus (Fig. 6A and B). If the capitellum were ossified, one would appreciate the maintained relationship of the radio-capitellar line on radiographs. A true elbow dislocation in this age group is rare and potentially nonexistent.

Figure 6.

Images courtesy of Arianna Trionfo, MD. A, B: AP and lateral radiographs of a newborn with a left humeral physeal separation. Note the absence of the capitellar ossification center, which may confuse the inexperienced clinician into a diagnosis of ulnohumeral dislocation. C: Lateral fluoroscopic image of contrast dye injected into the elbow. Note that the distal epiphyseal block is translated posteriorly. D: AP fluoroscopic image of the same elbow with contrast. E: After a closed reduction maneuver, the normal relationship of the distal physeal block to the diaphysis is re-established. F, G: AP and lateral fluoroscopic images of the same elbow after fixation with percutaneous pinning.

Both operative and nonoperative treatments have been described, but all descriptions are from case reports or small case series, many of which combine patients with distal humeral physeal separations from both birth trauma (neonates) and accidental/nonaccidental trauma (young children) [[36], [37], [38], [39], [40],42]. Although the injury is conceptually similar, there may be small differences between these two populations, adding a layer of difficulty when interpreting results. Regardless of treatment options, the most common residual result is malunion, which can present as a decreased range of motion or abnormalities in the carrying angle, most commonly cubitus varus [41,42]. Avascular necrosis of the trochlea and/or medial condyle leading to medial column collapse can also result in later-onset deformity [57,58].

Ratti et al. reviewed 20 case reports and case series of 33 newborns with distal humeral physeal separation, the vast majority of whom were treated conservatively (88%) [41]. In their review, the conservatively treated patients were treated with either cast, sling, or tape. Most patients had good prognoses, with 88% having a normal carrying angle and 80% having no range of motion deficits. Jacobsen et al. report complete remodeling in all patients with slight cubitus varus in one in a series of six newborns with distal humeral physeal separation treated with casting in a displaced position [36]. Hariharan et al. report the largest case series of 79 children treated surgically for distal humeral physeal separation [42]. Of their cohort, 7.6% had cubitus varus or valgus, and 4% had a decreased range of motion. However, only nine patients’ injuries were due to birth trauma, with the average age of their population at 18 months old. Their complication rate seemed to be influenced by time to surgery, with 60% of patients who experienced a complication presenting greater than 24 ​h after injury.

Surgical treatment is similar to that of supracondylar humerus fractures with closed reduction and percutaneous pinning. Arthrography may be used as a diagnostic adjunct to confirm the diagnosis of physeal separation and is often employed in the operating room to assess reduction (Fig. 6C–G). In our institution, we decide treatment based on time to diagnosis and after an informed discussion with the family. Further studies with a larger number of patients and longer follow-up are needed to determine the optimum treatment algorithm, but regardless of the treatment method chosen, patients generally do quite well with very little functional limitation. Cubitus varus, the most common complication in both operatively and nonoperatively treated infants can be addressed with distal humeral osteotomy if indicated when the child is older [59].

Proximal humeral physeal separation

Separation of the proximal humeral physis is the second-most common flavor of physeal separation due to birth trauma. These injuries can be found with brachial plexus palsy [60], but the vast majority are not [60]. Proximal humeral physeal separations must be distinguished from shoulder dislocations, either congenital or traumatic, a much rarer entity but which has been described [[61], [62], [63]]. Such differentiation can be accomplished by arthrogram, ultrasound, or MRI [[28], [29], [30],32,33]. We prefer ultrasound despite needing a skilled technician/radiologist, as it is the least invasive and doesn't require sedation.

While both operative and nonoperative modalities have been described, most of the humeral growth occurs at the proximal physis, with enormous remodeling potential. This allows complete remodeling of the most displaced injuries with no functional deficit in most patients [64]. There have been many case reports of infants with these injuries treated conservatively, with great results. One of the largest case series to date of neonates with this injury describes operative treatment after failed closed reduction, with open reduction through a deltopectoral approach and percutaneous Kirschner wire fixation [34]. They report excellent results in their surgically treated cohort. Despite these results, we advocate treating these injuries nonoperatively with soft swathing immobilization without an attempt at reduction, given the excellent remodeling potential of the proximal humerus, avoiding the inherent risks of surgery.

Distal femoral physeal separation

Distal femoral physeal separations from birth are rare, with only a handful of case reports and case series reported usually seen in breech patients [43,50,51,[65], [66], [67], [68], [69]]. The presentation is similar to other physeal injuries, which includes pain, swelling, and decreased motion. The differential diagnosis includes congenital knee dislocation, septic arthritis, and osteomyelitis, depending on the appearance of the limb and the overall clinical picture. The utility of plain radiographs to diagnose a distal femur-physeal separation due to birth trauma largely depends on the gestational age at the time of delivery. The ossific nucleus of the distal femur may not yet be present in a preterm infant. In neonates born at 29–36 weeks, the distal femur epiphyseal ossific nucleus is only 54% of the time on ultrasound [70,71]. If present, plain radiography can reveal a disruption of the normal spatial relationship of the distal femoral epiphyseal ossific nucleus with that of the shaft (Fig. 7A). If absent, roentgenographic diagnosis is difficult. Ultrasound or MRI is more useful for assessing diaphyseal-epiphyseal alignment in these situations to evaluate for physeal separation [67,69]. Arthrography is another adjunctive tool used preoperatively or intraoperatively to diagnose or evaluate the reduction quality (Fig. 7B and C).

Figure 7.

A: Lateral radiograph of the left lower extremity of a 7-day-old female who was referred from the pediatric team for “hip click/instability” (the hip was normal, and the instability was due to the unstable physeal separation). Note the relationship between the ossific nucleus of the distal femoral epiphysis–it is displaced posteriorly relative to the diaphysis. B, C: AP and lateral fluoroscopic images of the distal femur intraoperatively after an arthrogram, closed reduction, and percutaneous pin fixation. D, E: AP and lateral radiographs at age 14 days (1 week after surgery). There is abundant callus formation and periosteal bone formation. F, G: AP and lateral radiographs at age 3 months. There has been maturation of the extensive callus. H, I: AP and lateral radiographs at age 6 months. There has been significant remodeling and the double cortex sign is no longer apparent.

Both operative and nonoperative treatments have been described, with a lack of clear consensus or accepted standard of care due to the rarity of these injuries. We advocate for nonoperative treatment with immobilization for nondisplaced injuries or for those with a late diagnosis, in which the healing process is well along. Closed reduction followed by immobilization is attempted for those with displacement who are identified acutely, and percutaneous pin fixation can be added if instability remains after closed reduction (Fig. 7B–I) [66,72]. Open reduction may be indicated in cases in which closed reduction is unsuccessful [65]. At least in the short term, the prognosis appears to be good [43]; however, the literature supporting distal femoral physeal injuries due to birth trauma is sparse and of low-level evidence, and no long-term data exist.

Proximal femoral physeal separation

Proximal femoral physeal separation due to birth trauma is another rare entity with descriptions in case reports and case series predominantly of infants after difficult deliveries in the breech position, with macrosomia common as well [[52], [53], [54], [55]]. The incidence of these injuries is unknown. Like physeal separations of the distal femur, infants with this injury present with pseudoparalysis of the affected lower extremity, swelling, pain with attempted motion, and palpable crepitus in the acute period. This rare injury must be distinguished from the much more common dislocated hip in the setting of developmental dysplasia of the hip (DDH) or septic arthritis (Fig. 8A and B). Radiographically, lateral and superior displacement are seen, similar to DDH. The ossific nucleus is not yet ossified to differentiate physeal disruption from DDH roentgenographically. However, the acetabulum will not be dysplastic in physeal disruptions, unlike DDH, where the acetabular index is likely increased. Clinically, the child with DDH will not have pain, pseudoparalysis, or swelling. After a week or two, radiographs will reveal fracture callus in patients with physeal separation, differentiating them from those with DDH. As in other physeal injuries discussed previously, MRI, ultrasound, and arthrography can also aid in the diagnosis.

Figure 8.

Images courtesy of Ken Noonan, MD. Example of a hip dislocation secondary to septic arthritis in a neonate. A: AP pelvis radiograph showing a left hip dislocation in a 10-day-old male, concerning for septic arthritis given the clinical scenario. B: Postcontrast MRI image confirming septic arthritis.

Nonoperative treatment has been most commonly described [52,55], with casting, bracing, or double-diapering immobilization. Reports of operative treatment consisting of open reduction with pin fixation have also been described [54]. A good clinical prognosis is expected regardless of treatment, with some mild deformities reported in a few patients, such as proximal femoral valgus or mild anterior bowing of the femur [52,55]. In contrast to femoral neck fractures in older children, avascular necrosis (AVN) in neonates after proximal femoral physeal separation has not been described. This is likely since the injury mechanism leaves the posterior periosteal sleeve intact. Ogden et al. examined cadaveric specimens of six stillborn neonates after inducing such an injury and found the posterior periosteum intact in all specimens, with an undisturbed hip capsule. Since the blood supply enters the femoral head posteriorly, this is seemingly protective against AVN. Indeed, observations of earlier-than-expected proximal femoral ossific nucleus formation after healing of these injuries have been noted, indicating adequate (increased, in fact) blood flow due to the healing response [52].

Summary

Fractures due to birth trauma are rare and easily missed in the acute period. A high index of suspicion is required for clinicians to reduce the number of these injuries that initially pass undetected from notice. Although the prognosis is excellent in most cases, appropriate treatment after timely recognition pays dividends in earning parental trust. A low threshold for additional imaging (ultrasound) is recommended as the radiographic appearance of physeal injuries is often ambiguous with other diagnoses. Nonoperative management can be offered most of the time, but operative treatment has a role in select indications.

Additional links

• •POSNAcademy: Staying out of trouble with pediatric elbow fractures

Consent for publication

The author(s) declare that no patient consent was necessary as no images or identifying information are included in the article.

Author contributions

Tyler C. McDonald: Writing – review & editing, Writing – original draft, Investigation, Conceptualization. C. Lake Higdon: Writing – review & editing, Writing – original draft, Investigation. William A. Cutchen: Writing – review & editing, Writing – original draft, Investigation.

Funding

None.

Declaration of competing interests

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.