THUMB PROXIMAL PHALANX FRACTURE PEDIATRIC

Fracture Nomenclature for Thumb Proximal Phalanx Fracture Pediatric

Hand Surgery Resource’s Diagnostic Guides describe fractures by the anatomical name of the fractured bone and then characterize the fracture by the Acronym:

In addition, anatomically named fractures are often also identified by specific eponyms or other special features.

For the Thumb Proximal Phalanx Fracture Pediatric, the historical and specifically named fractures include:

Salter-Harris avulsion fracture of the UCL

Proximal phalanx neck fracture

Complex MP joint dislocation

By selecting the name (diagnosis), you will be linked to the introduction section of this Diagnostic Guide dedicated to the selected fracture eponym.

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The hand is the most commonly fractured location in children, and the majority of these fractures affect the phalanges. Of the phalanges, the proximal phalanx is most frequently involved, and the thumb ranks second behind the little finger in terms of fracture frequency in the digits of children. Sporting activities—like skiing and biking—are often responsible for these types of injuries, fractures and fracture-dislocations.  Fracture-dislocations are more common than true dislocations because younger bones, especially at the growth plate, are more fragile than the ligaments. In addition, age has an effect on the type of fracture sustained, as Salter-Harris type II fractures appear to be the dominant fracture of the proximal phalanx base among children aged <10 years, while Salter-Harris type III fractures are most common in adolescents older than 11 years. Although pediatric fractures share some similarities with their adult counterparts, the presence of physes and other developmental changes in children and adolescents makes it requisite that careful consideration be given to these factors to ensure appropriate diagnosis and management.^1-5

Definitions

• A pediatric thumb proximal phalanx fracture is a disruption of the mechanical integrity of the thumb proximal phalanx.
• A pediatric thumb proximal phalanx fracture produces a discontinuity in the proximal phalanx contours that can be complete or incomplete.
• A pediatric thumb proximal phalanx fracture is caused by a direct force that exceeds the breaking point of the bone.

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Hand Surgery Resource’s Fracture Description and Characterization Acronym

SPORADIC

S – Stability; P – Pattern; O – Open; R – Rotation; A – Angulation; D – Displacement; I – Intra-articular; C – Closed

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S - Stability (stable or unstable)

• Universally accepted definitions of clinical fracture stability is not well defined in the hand surgery literature.^6-8
• Stable: fracture fragment pattern is generally nondisplaced or minimally displaced. It does not require reduction, and the fracture fragments’ alignment is maintained with simple splinting. However, most definitions define a stable fracture as one that will maintain anatomical alignment after a simple closed reduction and splinting. Some authors add that stable fractures remain aligned, even when adjacent joints are put to a partial range of motion (ROM).
• Unstable: will not remain anatomically or nearly anatomically aligned after a successful closed reduction and simple splinting. Typically unstable pediatric thumb proximal phalanx fractures have significant deformity with comminution, displacement, angulation, and/or shortening.
• In the pediatric population, even most displaced fractures are easily reduced closed and often quite stable.⁵

P - Pattern

• Thumb proximal phalanx head: oblique, transverse, or comminuted; can involve the interphalangeal (IP) joint; these are intra-articular fractures that usually affect one or both condyles of the thumb proximal phalanx head with or without displacement; displaced fractures can affect joint congruity.
• Thumb proximal phalanx neck: fractures of the neck of the phalanges occur almost exclusively in children and are most common in the proximal phalanx; these fractures occur distal to the collateral ligament recess of the proximal phalanx, and presenting patients typically have apex volar angulation with associated sagittal and subcondylar malalignment.^4,5,9,10
• Thumb proximal phalanx shaft: transverse, oblique, or comminuted, with or without shortening; these fractures are less common than other proximal phalanx fractures.¹¹
• Thumb proximal phalanx base: the most common site of injury in the bone, these fractures typically occur when the finger is abducted past the normal range of the metacarpophalangeal (MP) joint.^4,11,12 May be intra- or extra-articular and usually involves the dorsal or volar lip of the proximal phalanx base.¹⁰
• Intra-articular fractures are associated with concomitant injury of the ulnar collateral ligament (UCL).¹⁰

O - Open

• Open: a wound connects the external environment to the fracture site. The wound provides a pathway for bacteria to reach and infect the fracture site. As a result, there is always a risk for chronic osteomyelitis. Therefore, open fractures of the pediatric thumb proximal phalanx require antibiotics with surgical irrigation and wound debridement.^6,13,14

R - Rotation

• Pediatric thumb proximal phalanx fracture deformity can be caused by rotation of the distal fragment on the proximal fragment.
• Degree of malrotation of the fracture fragments can be used to describe the fracture deformity; this is not a common type of fracture deformity in the pediatric thumb proximal phalanx.
• Radial or ulnar deviation and malrotation of pediatric thumb proximal phalanx neck fractures are also possible, and radiographs can underestimate the degree of clinical rotational deformity.⁵
• Some pediatric thumb proximal phalanx fractures will have substantial rotational deformities that can only be detected through clinical evaluation.¹¹
• Salter-Harris fractures of the pediatric thumb proximal phalanx with associated rotational deformity require appropriate management, as the deformity can persist if left untreated, i.e. rotational deformities are not as likely to correct with remodeling and growth as other fracture deformities.¹

A - Angulation (fracture fragments in relationship to one another)

• Angulation is measured in degrees after identifying the direction of the apex of the angulation.
• Straight: no angulatory deformity
• Angulated: bent at the fracture site
• Example: pediatric thumb proximal phalanx neck fractures usually have apex volar angulation with associated sagittal and subcondylar malalignment.⁴

D - Displacement (contour)

• Displaced: disrupted cortical contours
• Nondisplaced: fracture line defining one or several fracture fragments; however, the external cortical contours are not significantly disrupted
• Pediatric thumb proximal phalanx neck fractures are prone to proximal displacement, and most are displaced with dorsal translation and extension angulation.^5,12
• Displaced epiphyseal fractures of the pediatric thumb proximal phalanx will result in articular and physeal incongruity and therefore require surgery.¹⁵

I - Intra-articular involvement

• Fractures that enter a joint with one or more of their fracture lines.
• Pediatric thumb proximal phalanx fractures can have fragment involvement with the IP or MP joints.
• If a fracture line enters a joint but does not displace the articular surface of the joint, then it is unlikely that this fracture will predispose to posttraumatic osteoarthritis. If the articular surface is separated or there is a step-off in the articular surface then the congruity of the joint will be compromised and the risk of posttraumatic osteoarthritis increases significantly.

C - Closed

• Closed: no associated wounds; the external environment has no connection to the fracture site or any of the fracture fragments.^6-8

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Pediatric thumb proximal phalanx fractures: named fractures, fractures with eponyms and other special fractures

Salter-Harris avulsion fracture of the UCL

• Injuries to the UCL at the thumb’s proximal phalanx base are less common and not as thoroughly described in children compared to those in the adult population. As in adults, these injuries result from a hyperabduction force applied to an extended thumb, and sporting activities like skiing and biking are often responsible.^16,17
• The primary difference between these injuries is the anatomy of the pediatric thumb, as the UCL runs from the head of the metacarpal to the inner aspect of the proximal phalanx base, where it connects almost entirely to the epiphysis. Due to this anatomy, hyperabduction rarely results in an isolated rupture of the UCL, but instead tends to cause intra-articular fracture at the base of the thumb.^15,18  These are primarily Salter-Harris fractures due to their frequent involvement of the physes. Salter-Harris avulsion fractures of the UCL at the ulnar portion of the epiphysis are considered to be the pediatric equivalent of “bony skier’s thumb.”^10,15
• Rupture or avulsion of the insertion or origin of the UCL can also result in these injuries.^2,16  It is generally accepted that Salter-Harris type III fractures are the most common fractures of the thumb proximal phalanx base in adolescents aged ≥11 years because the central part of the physis begins to close around this age. Agreement on the most prevalent type of base fracture in children younger than 10 years, however, is less certain, which led to a prospective study on 58 children in this age cohort.
• Results showed that that Salter-Harris type II was the most common fracture type in children aged <10 years, accounting for 72% of these fractures. There were no Salter-Harris type III, IV, or V fractures in this cohort.³
• By contrast, another similar study found juxta-epiphyseal II fractures to be the most common fracture type in the proximal phalanx base of the other fingers of children. This may be related to the microscopic anatomy of the physis and metaphysis in these bones.¹⁹
• These injuries destabilize the first MP joint and result in loss of thumb pinch and grip power if not properly treated. A displaced epiphyseal fracture of the proximal phalanx will also result in articular and physeal incongruity.^10,15
• Although isolated rupture of the UCL of the thumb in children is rare, it is still important to suspect it in these injuries. Surgical exploration and/or MRI may also be necessary to determine if a Stener lesion is present, as missing this type of lesion can lead to long-term disability.¹⁸

Imaging

• Posteroanterior, lateral and oblique X-ray views are recommended, but it is important to note that some epiphyseal fractures will have normal X-rays, and surgical exploration may therefore be necessary.^3,16
• Stress radiographs and advanced imaging studies (eg, ultrasound, MRI, arthrogram) should only performed in ambiguous cases.²

Treatment

• Nondisplaced fractures should be treated by cast immobilization for 4-6 weeks, while displaced fractures typically require surgical intervention to evaluate the displacement of the UCL or fracture fragment outside the adductor aponeurosis, such as a Stener lesion.^2,20
• Displaced Salter-Harris III fractures at the base of the thumb proximal phalanx (displaced >1.5 mm or rotated fragment) require open reduction and internal fixation (ORIF) to restore the integrity of the UCL and to obtain a congruous joint surface.²
  • The surgical technique should include a longitudinal incision along the attachment site of the adductor aponeurosis into the extensor pollicis longus (EPL), which allows for a longitudinal arthrotomy. The fracture fragment and joint surface should then be inspected and the type of fixation selected.
• There are multiple fixation options, which include K-wire fixation, tension wire fixation, and mini-screw placement.
• Closure requires careful repair of the adductor aponeurosis to the EPL, and a thumb spica cast that covers the percutaneous K-wire should be applied.
• The K-wire is then removed 4 weeks after surgery and ROM is started. A splint is fabricated to protect the repair during activities for 1 additional month.²
• Chronic pediatric UCL injuries are more difficult to manage, and UCL reconstruction is complicated, especially in young children with an open physis. Chrondrodesis with an attempt to preserve the physis or arthrodesis may be the most reliable option.²

Complications

• MP joint instability
• Nonunion
• Malunion
• Impaired grip/pinch strength
• Posttraumatic osteoarthritis

Outcomes

• One 9-year-old girl with a Salter-Harris II fracture at the base of her thumb proximal phalanx with rotational deformity was treated with closed reduction consisting of retraction and derotation of the fracture. Results were successful and resolved the rotational deformity.¹

Proximal phalanx neck fracture

• These transverse extra-articular fractures through the neck of the proximal phalanx occur almost exclusively in the pediatric population. Also known as subcapital, subcondylar, and supracondylar phalangeal fractures, these injuries may be either displaced or nondisplaced.^3,21
• In almost all cases, proximal phalanx neck fractures result from the thumb being entrapped in a closing door. It is thought that displacement of the distal fragment occurs as the child violently attempts to withdraw the trapped thumb, and the withdrawal opens the fracture site enough for rotation of the distal fragment to occur.³
• Nonunion in these fractures is rare, but the following factors may increase the risk for it developing:
  • Younger age group with incomplete ossification of condyles
  • Displaced fractures
  • Failure to obtain a true lateral X-ray
  • Inadequate initial management by closed reduction and splinting
  • Delay of K-wire fixation beyond 3 weeks of injury
  • Premature removal of the K-wire used to fix the fracture^3,22

Imaging

• A lateral radiographic view is best for diagnosing these injuries, as an anteroposterior view can easily miss the fracture.

Treatment

• Most nondisplaced thumb proximal phalanx neck fractures can be treated with splinting. Displaced fractures, however, are usually unstable after closed reduction, and ORIF with K-wire fixation is therefore required in most of these cases. Without surgical intervention, there is a significant risk of malunion and nonunion.³
  • In most of these fractures, K-wires should be left in place for 3-6 weeks.³
  • In severely displaced fractures, the distal fragment can rotate to as much as 180°.²¹
• Nonunion is these cases is rare, but if it does develop, the treatment of choice is bone grafting.³
  • This may be accomplished with either cancellous or corticocancellous bone grafts.²²
  • The ideal time for treating nonunion with bone grafting is during childhood, but delayed grafting may be needed in cases of neglected nonunion.²²

Complications

• Nonunion
• Avascular necrosis
• Malunion

Outcomes

• In one study, a series of 4 patients had established nonunion after failed closed reduction and splinting. They were referred for additional treatment 6-8 months after the initial injury and underwent iliac crest bone grafting.
  • Radiological union was observed in all cases after 6 weeks, and all thumbs were clinically stable, with no pain on manipulation after removal of the K-wire.
  • At the final follow-up 1-2 years later, all patients had normal ROM at the MP and basal joints of the thumb.²¹
• Another study of adults with neglected nonunion resulting from thumb proximal phalanx fractures earlier in life were treated surgically with delayed iliac crest bone grafting. This intervention led to positive functional outcomes and a high patient satisfaction rate.²²

Complex MP joint dislocation (Without Fracture)

• Dislocation of the thumb’s MP joint in children is uncommon on account of their bones being weaker than the surrounding ligaments and soft tissues. These injuries usually stem from an axial blow causing forced hyperextension of the MP joint, with sporting activities and fall on an outstretched hand (FOOSH) injuries often being responsible.^23-25
• Pediatric MP dislocations at the thumb can be classified as one of three types:
  • Incomplete dislocation: the collateral ligaments are intact, and the injury can be managed by closed reduction.
  • Simple complete dislocation: the volar plate and collateral ligaments rupture, but the volar plate is not interposed in the joint, which usually presents as hyperextension deformity. Can also be managed by closed reduction.
  • Complex complete dislocation: the volar plate is displaced—possibly due to an avulsion fracture—and interposed in the joint, with the metacarpal and proximal phalanx usually lying parallel to each other. This type of dislocation is uncommon.  These fracture-dislocations are irreducible injuries that require surgical intervention.  Other interposed obstacles that may prevent closed reduction include flexor tendons, the collateral ligaments, the joint capsule, and sesamoid bones.^24. Most pediatric MP joint dislocations are dorsal, with volar dislocations being extremely rare. ^23,24

Imaging

• Anteroposterior, lateral, and oblique X-ray views are needed, with the lateral view being most helpful.

Treatment

• Incomplete and simple complete MP dislocations can be effectively treated with closed reduction—which may be accomplished with the McLaughlin technique—and brief periods of immobilization followed by mobilization exercises to prevent joint stiffness.²⁴
  • Repeated attempts at close reduction should be avoided, because this can convert a simple dislocation into a complex complete dislocation. This is also possible when the proper reduction technique is not used for these injuries, and open reduction may therefore be needed in cases of failed or improper closed reduction.^24,25
• Because complex complete MP dislocations are irreducible, open reduction is needed, which may be performed with either a dorsal or volar approach.²⁴
  • The optimal treatment option is still controversial, and the choice depends on the surgeon’s preference and presence of concomitant injuries.²⁵
  • The volar approach carries a higher risk of neurovascular injury due to the anatomy and location of neurovascular bundles, but the volar plate can be directly visualised and repaired easily when using it.^24,25
  • The dorsal approach allows for surgical exploration of the MP joint and provides excellent exposure of the volar plate, but its disadvantage is the longitudinal splitting of the volar plate to reduce the MP joint, which is irreparable.^24,25
  • If using a volar approach, extreme care is necessary to protect the displaced radial digital neurovascular pedicle. Early protected mobilization is also important to lessen the risk of stiffness.¹⁵
  • Arthroscopic reduction is another technically demanding surgical option that may be considered.²⁵
  • Immobilization with a thumb spica cast for approximately 4 weeks, followed by active ROM exercises, is necessary after all cases of open reduction.²⁴

Complications

• Stiffness
• Premature physis closure
• Posttraumatic osteoarthritis
• Osteonecrosis

Outcomes

• Studies on outcomes after treating children with MP dislocations of the thumb are scarce.²⁴
• In one study on 10 patients with MP dislocations, incomplete and simple complete dislocations were managed with closed reduction using the McLaughlin technique, while irreducible dislocations were managed with open reduction using either a volar or dorsal approach.
  • Of the 10 patients, 9 had excellent results at the final follow-up, regaining full painless ROM at the MP joint without any instability, and they also achieved good pinch strength. Mild stiffness in one patient treated with open reduction was likely due to him presenting on the fourth day after trauma and his lack of compliance with physical therapy.²⁴
• In another study of 37 pediatric patients with MP joint dislocation, 33 were treated with closed reduction and 4 required open reduction.
  • Of these patients, 35 had excellent results at follow-up, with normal ROM of the MP and no pain. There was also no incidence of infection, recurrent dislocation, or severe stiffness.²³

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Related Anatomy

• The pediatric thumb proximal phalanx consists of a distal phalangeal head that articulates at the IP joint with the distal phalanx, a supportive neck, a narrow diaphyseal shaft, a proximal metaphysis, and a base that articulates at the MP joint with the thumb metacarpal. The physis is located at the base of the proximal phalanx, which has a dorsal and volar lip and is most susceptible to fracture along the thumb ray.^2,4
• The ligaments associated with the thumb proximal phalanx at the IP and MP joints are the joint capsule, the proper and accessory UCL and radial collateral ligament (RCL), and the volar plates. The collateral ligaments about the MP joint originate from the metacarpal epiphysis and insert almost entirely on the epiphysis of the proximal phalanx, while the collaterals about the IP joint originate from the phalangeal head, cross the physis, and insert onto the metaphysis and epiphysis of the distal phalanges. This configuration partially explains why Salter-Harris III fractures are so common at the thumb MP joint, and Salter-Harris II fractures at the IP joint.²
• Tendon attachments of the thumb proximal phalanx include the abductor pollicis brevis, flexor pollicis brevis, opponens pollicis, and extensor pollicis brevis, which inserts onto the epiphysis of the proximal phalanx.²

Incidence and Related injuries/conditions

• Metacarpal and phalangeal fractures account for about 21% of all pediatric fractures, and the phalanges are the most commonly injured hand bones in this population.^4,10
• The annual incidence of phalangeal fractures in children and adolescents up to 19 years old is approximately 2.7%.²⁶
• The proximal phalanx is the most frequently fractured phalangeal bone in the pediatric population. These fractures are about twice as common as those of the distal and middle phalanges.^27-29
• The little finger is the most commonly fractured digit, followed by the thumb.^28-30
  • In one study, the incidence of thumb fracture was found to be low in children less than 10 years of age, but a steep rise was noted after this age, which led to the thumb becoming the second most commonly fractured ray in adolescents.²⁸
  • In the thumb, the proximal phalanx (52%) was more frequently fractured than the metacarpal (31%) and distal phalanx (17%).²⁸
• The incidence of all phalangeal fractures is highest in children aged 10-14 years, which coincides with the time that most children begin playing contact sports.⁴
• Despite the fact that most patients are right-hand dominant, the distribution of phalangeal fractures is generally found to be similar in both the right and left hands.^28,30
• Physeal injuries account for 15-30% of all pediatric fractures, and significant growth disturbance may occur in approximately 10% of cases. These types of injuries are most common during the adolescent growth spurt between ages 10-16, and are more common in boys than in girls.³⁰
  • Salter-Harris II fractures have been shown to have an incidence of 39% of hand fractures overall, and they represent approximately 90% of all Salter-Harris fractures in the hand.³²

A classic patient is an 8-year-old, left-handed boy who injured himself in a biking accident. While riding his bike at a fast speed, the boy failed to avoid a large pothole and hit it head-on, which caused the bike to flip forward and his body to sail over the handlebars. The boy landed hard on his outstretched hands, with the brunt of the impact being concentrated on his right thumb. The force caused an extreme hyperabduction of the thumb that resulted in a Salter-Harris II avulsion fracture at the base of his thumb’s proximal phalanx. Severe pain and swelling resulted, and the boy went to the emergency department for treatment. 

• The care and precautions related to immobilization devices for the pediatric thumb proximal phalanx fracture must be carefully reviewed with the patient. Patients should be educated regarding care and precautions. Patients should know that pain, especially increasing pain, numbness, tingling, skin irritation, splint loosening, or excessive splint tightness are red flags and should be reported to the surgeon or his team.
• Pain should be managed with properly fitting splints, reassurance, elevation, ice in the initial post-fracture period, and mild pain medications. Patients should be encouraged to discontinue pain medication as soon as possible. Opioid use should be kept to a minimum.
• Patients should be instructed to carefully exercise all joints in the injured hand that do not require immobilization. Patients usually can exercise on their own; however, signs of generalized finger or hand stiffness are indications for referral to hand therapy (PT or OT).  If surgery is performed, early, self-directed, active ROM exercises of the thumb are recommended after pin and cast removal.³⁷
• Fractures that require internal fixation can be mobilized after 4 weeks.
• If an infection does occur, management should focus on eradicating sepsis with thorough debridement, appropriate antibiotics (eg, cephalosporin, penicillin), and fracture stabilization, followed by obtaining fracture union and regaining a functional extremity.³⁸

• Although stiffness is possible in pediatric patients, it is not as significant of a concern as it is in adults. This makes cast immobilization a more feasible option when treating pediatric thumb proximal phalanx fractures.⁵
• Failure to protect the pins in a cast until fracture healing could allow redisplacement and malunion of the fracture, which is much more difficult to address than stiffness in the pediatric population.⁵
• Malunion and deformity after pediatric thumb proximal phalanx fractures is rare but can occur, especially in open, severe, unstable fractures.³⁹
  • Surgical procedures to correct for malunions have a higher complication rate and require a great deal of technical skill, which is why prevention that focuses on early recognition and intervention is imperative.¹
• Nonunion without avascular necrosis is more common after phalangeal neck fractures of the thumb than the fingers, and the resulting instability requires bone grafting.²¹
• Posttraumatic osteoarthritis can occur in the IP or MP joint after some pediatric proximal phalanx fractures.
• Chronic osteomyelitis of the thumb proximal phalanx is rare but can occur in open fractures, especially in patients with diabetes or in patients whose immune system is compromised.

• Most outcomes after pediatric thumb proximal phalanx fractures are good.^21-24 Fortunately, the complications noted above are very rare. Significant stiffness can usually be avoided because the IP joint of the thumb can be mobilized while the MP joint and proximal phalanx are splinted.
• Although several factors can influence the healing process of the fracture—such as patient age, blood supply to the epiphysis, method of reduction, and whether the injury is open or closed—Salter-Harris types I, II, and III fractures are often associated with a good prognosis.¹

• Pediatric thumb proximal phalanx fractures must be immobilized before radiographic fracture remodeling is complete to avoid disabling stiffness.
• Immobilization of pediatric thumb proximal phalanx fractures for >4 weeks is rarely needed.²⁷
• Today, as in ancient times, most pediatric thumb proximal phalanx fractures can be treated without surgery.^8,38
• Underlying pathological conditions such as bone tumors like enchondromas and osteoporosis should be expected in fractures that occur from trivial trauma.
• The functional needs of each patient must be considered when recommending treatment for finger fractures.
• The phalangeal physes remain open until approximately age 16.5 in males and 14.5 in females, and knowledge of these growth centers is important because iatrogenic physeal arrest may occur in patients with physeal injuries or those who undergo multiple fracture reduction attempts.^4. These repeated attempts can crush and disrupt the layered order of the physis, which is why if a reduction cannot be accomplished in 1 or 2 attempts, it is better to consider a controlled open operative reduction to reduce the chance of arrest.¹¹
• An unmineralized physis is biomechanically weaker than the surrounding ligamentous structures and mature bone, which makes fractures of the physes more likely compared with ligamentous injuries or diaphyseal fractures.^4. The physes are particularly vulnerable in younger children when shear forces are applied to the thumb, stressing the attachments of the chondrocytes at the zone of proliferation.¹¹
• Despite the general ease of treatment and good outcomes of many pediatric thumb proximal phalanx fractures, it is essential to carefully and thoroughly evaluate each injury to consider the possibility of any special fractures that may require a more intense course of treatment. Most complications in treating these pediatric patients occur because the severity of the injury is underestimated on initial evaluation.⁵
• Salter-Harris type I fractures only account for about 2% of all proximal phalanx injuries, must still be recognized. Radiographs of these injuries may not reveal any displacement, but deformity may still be detected in the clinical examination. If this fracture is identified early, treatment will be simple and residual deformity can be avoided.⁴⁰
• Minimally displaced and stable pediatric thumb proximal phalanx fractures require minimal augmentation due to their inherent stability and rapid fracture healing. The periosteum can be a powerful tool for reduction in children, providing a "hinge" to lever the distal segment on the proximal portion of the bone to attain anatomic alignment.¹¹
• Evaluating an injured thumb in children is often challenging, as many are often noncompliant, scared, and/or unable to understand instructions. Observation and play must therefore provide clues to the extent of the injury. The wrinkle test may also be needed to assess nerve integrity.²
• It is extremely important to look for rotational deformities during the physical examination of Salter-Harris fractures of the thumb in order to prevent future residual deformities.¹
• Special X-ray views: 1:Lateral and oblique radiographs are often necessary to identify and understand the fracture pattern.⁴  2.Because the thumb is rotated 90° to the palm, anteroposterior and lateral radiographs of the thumb should be directed at the thumb and not the fingers.²  3.The lack of ossification in the immature skeleton obscures bony details and complicates radiograph interpretation, and comparison with the noninjured hand is often needed.²
• Advanced imaging is usually not necessary, but an MRI, CT scan, or ultrasound may be warranted in certain cases.⁴

New and Cited Articles

1. Izadpanah A, Karunanayake M, Izadpanah A, et al. Salter-harris type 2 fracture of the proximal phalanx of the thumb with a rotational deformity: a case report and review. Pediatr Emerg Care 2012;28(3):288-91. PMID: 22391929
2. Kozin SH. Fractures and dislocations along the pediatric thumb ray. Hand Clin 2006;22(1):19-29. PMID: 16504775
3. Al-Qattan MM, Al-Zahrani K, Al-Boukai AA. The relative incidence of fractures at the base of the proximal phalanx of the thumb in children. J Hand Surg Eur Vol 2009;34(1):110-4. PMID: 18936134
4. Abzug JM, Dua K, Bauer AS, et al. Pediatric Phalanx Fractures. J Am Acad Orthop Surg 2016;24(11):e174-e183. PMID: 27755266
5. Cornwall R, Ricchetti ET. Pediatric phalanx fractures: unique challenges and pitfalls. Clin Orthop Relat Res 2006;445:146-56. PMID: 16505727
6. Cheah AE, Yao J. Hand Fractures: Indications, the Tried and True and New Innovations. J Hand Surg Am 2016;41:712-22. PMID: 27113910
7. Nesbitt KS, Failla JM, Les C. Assessment of instability factors in adult distal radius fractures. J Hand Surg Am 2004;29:1128-38. PMID: 15576227
8. Walenkamp MM, Vos LM, Strackee SD, Goslings JC, Schep NW. The Unstable Distal Radius Fracture-How Do We Define It? A Systematic Review. J Wrist Surg 2015;4:307-16. PMID: 26649263
9. Al-Qattan MM, Cardoso E, Hassanain J, et al. Nonunion following subcapital (neck) fractures of the proximal phalanx of the thumb in children. J Hand Surg Br 1999;24(6):693-8. PMID: 10672806
10. Sivit AP, Dupont EP, Sivit CJ. Pediatric hand injuries: essentials you need to know. Emerg Radiol 2014;21(2):197-206. PMID: 24158746
11. Nellans KW, Chung KC. Pediatric hand fractures. Hand Clin 2013;29(4):569-78. PMID: 24209954
12. Williams AA, Lochner HV. Pediatric hand and wrist injuries. Curr Rev Musculoskelet Med 2013;6(1):18-25. PMID: 23264097
13. Ketonis C, Dwyer J, Ilyas AM. Timing of Debridement and Infection Rates in Open Fractures of the Hand: A Systematic Review. Hand (N Y) 2017;12:119-26. PMID: 28344521
14. Meals C, Meals R. Hand fractures: a review of current treatment strategies. J Hand Surg Am 2013;38:1021-31. PMID: 23618458
15. Waters PM. Problematic pediatric wrist and hand injuries. J Pediatr Orthop 2010;30; Suppl 2:S90-S5. Link
16. White GM. Ligamentous avulsion of the ulnar collateral ligament of the thumb of a child. J Hand Surg Am 1986;11(5):669-72. PMID: 3760492
17. Mintzer CM, Waters PM. Late presentation of a ligamentous ulnar collateral ligament injury in a child. J Hand Surg Am 1994;19(6):1048-9. PMID: 7876480
18. Wallace DA, Carr AJ. Rupture of the ulnar collateral ligament of the thumb in a 5-year-old girl. J Hand Surg Br 1993;18(4):501. PMID: 8409668
19. Al-Qattan MM, Al-Zahrani K, Al-Boukai AA. The relative incidence of fractures at the base of the proximal phalanx of the fingers in children. J Hand Surg Eur Vol 2008;33(4):465-8. PMID: 18687834
20. Davies MB, Wright JE, Edwards MS. True skier's thumb in childhood. Injury 2002;33(2):186-7. PMID: 11890924
21. Al-Qattan MM. Nonunion and avascular necrosis following phalangeal neck fractures in children. J Hand Surg Am 2010;35(8):1269-74. PMID: 20684927
22. Al-Qattan MM. Neglected nonunion of phalangeal neck fractures of the thumb in children: the outcome of delayed bone grafting in adulthood. Ann Plast Surg 2012;68(3):276-8. PMID: 21629085
23. Maheshwari R, Sharma H, Duncan RD. Metacarpophalangeal joint dislocation of the thumb in children. J Bone Joint Surg Br 2007;89(2):227-9. PMID: 17322440
24. Khursheed O, Haq A, Rashid S, et al. Clinical Outcome of Metacarpophalangeal Joint Dislocation of the Thumb in Children: Case Series of 10 Patients. J Hand Microsurg 2016;8(1):13-6. PMID: 27616822
25. Blucher N, Srinivasan S, Bass A. Delayed Presentation of Metacarpophalangeal Joint Dislocation of the Thumb in Children Requiring Open Reduction: Two Cases Reported and Review ofLiterature. J Orthop Case Rep 2015;5(3):5-8. PMID: 27299055
26. Naranje SM, Erali RA, Warner WC Jr, et al. Epidemiology of Pediatric Fractures Presenting to Emergency Departments in the United States. J Pediatr Orthop 2016;36(4):e45-8. PMID: 26177059
27. Rodríguez-Vega V, Pretell-Mazzini J, Marti-Ciruelos R, et al. Simultaneous juxta-epiphyseal proximal phalanx fracture with flexor tendon entrapment in a child: a case report and review of literature. J Pediatr Orthop B 2013;22(2):148-52. PMID: 22561910
28. Vadivelu R, Dias JJ, Burke FD, Stanton J. Hand injuries in children: a prospective study. J Pediatr Orthop 2006;26(1):29-35. PMID: 16439897
29. Liu EH, Alqahtani S, Alsaaran RN, et al. A prospective study of pediatric hand fractures and review of the literature. Pediatr Emerg Care 2014;30(5):299-304. PMID: 24759492
30. Chew EM, Chong AK. Hand fractures in children: epidemiology and misdiagnosis in a tertiary referral hospital. J Hand Surg Am 2012;37(8):1684-8. PMID: 22763063
31. Menckhoff C. Pediatric Hand Injuries, Part I: Fractures and Dislocations. Ped Em Med Rep 2009. Link
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Reviews

1. Kozin SH. Fractures and dislocations along the pediatric thumb ray. Hand Clin 2006;22(1):19-29. PMID: 16504775
2. Izadpanah A, Karunanayake M, Izadpanah A, et al. Salter-harris type 2 fracture of the proximal phalanx of the thumb with a rotational deformity: a case report and review. Pediatr Emerg Care 2012;28(3):288-91. PMID: 22391929

Classics

1. Barton NJ. Fractures of the phalanges of the hand in children. Hand 1979;11(2):134-43. PMID: 488788
2. Hastings H, Simmons BP. Hand fractures in children. A statistical analysis. Clin Orthop Relat Res 1984;(188):120-30. PMID: 6467708