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Buckled, Bent Or Broken? CLINICAL Buckled, bent or broken? A guide to paediatric forearm fractures Gajan Selvakumaran, Nicole Williams THE RADIUS AND ULNA are the long bones ‘scissors’ adducts the thumb, abducts the fractured most commonly in school-aged index and middle fingers, and flexes the children, accounting for 40% of fractures.1,2 ring and small fingers to test the ulnar Background The radius and ulna are the most Forearm fractures occur at a rate of 1.5 nerve supply to the intrinsic hand muscles, commonly fractured long bones in the per child, with the ratio of affected boys and the ‘okay’ position isolates the anterior school-aged population, accounting for to girls increasing to 5.5:1 at adolescence. interosseous branch of the median nerve 40% of all fractures. Management of For children over the age of eight years, with flexion of the thumb and index finger individual fractures depends on the the distal radius is the site of 25% of to form a circle. Sensation is examined on fracture pattern and age of the child. all fractures.2 the first webspace dorsally (radial nerve), Objective Fracture management is guided by the and the pads of the index finger (median The aim of this article is to provide an fracture pattern and remodelling potential. nerve) and small finger (ulnar nerve). overview of the management concepts The aim of this article is to provide an Demonstrating with the uninjured hand for specific fracture patterns and support overview of management concepts and first can build trust. general practitioners to confidently support general practitioners to confidently The pain felt by most patients presenting manage these fractures and refer to manage these fractures and refer to to general practice with a fracture can orthopaedic services when required. orthopaedic services when required. be relieved with oral paracetamol and Discussion nonsteroidal anti-inflammatory drugs, with Orthopaedic advice and/or referral are a small sip of water if fasting for potential recommended for unstable fracture Initial assessment surgery. Nitrous oxide or intranasal or types (greenstick and complete oral opioids may facilitate splinting and fractures), particularly in older children The mechanism of injury may suggest where remodelling potential is minimal. the likelihood of fracture as well as type transport in more severe cases. Early referral for growth plate injuries of fracture sustained. It is important and suspected Monteggia and Galeazzi to remember that wrist sprains are injuries is warranted to minimise uncommon in children.3 Additional Fracture types long-term complications. injuries should be sought, such as a distal Torus (buckle) fractures humerus fracture in association with a The anatomical term ‘torus’ refers to fracture at the wrist. Past history may a rounded protuberance.5 Also called provide insight into pathological fractures. a ‘buckle’ fracture, torus fractures are The possibility of non-accidental injury characterised by buckling of one or should be considered. more cortices of the bone as a result of a Documentation of neurovascular compressive force, typically a fall from status is essential before and after any standing height onto the outstretched intervention, including cast or splint hand. These fractures usually occur in application. A simple screening aid for children <10 years, and the distal radius neurovascular injury in children is to play and/or ulna metaphysis is the most ‘rock, paper, scissors, okay?’4 ‘Rock’ tests common site. The majority of the cortex the median nerve supply to the finger remains intact, and torus fractures are flexors, ‘paper’ tests the radial nerve therefore inherently stable. They can be supply to wrist and finger extensors, managed appropriately with a range of 740 | REPRINTED FROM AJGP VOL. 49, NO. 11, NOVEMBER 2020 © The Royal Australian College of General Practitioners 2020 A GUIDE TO PAEDIATRIC FOREARM FRACTURES CLINICAL immobilisation methods from casts to those aged <8–10 years, and those aged with immobilisation that does not extend removable splints,6,7 balancing adequate ≥10 years. Fifteen-degree angulation and above the elbow. In young children, immobilisation for pain relief against 45° malrotation are considered acceptable extending the splint or cast above the compliance, convenience and costs in children aged <10 years, while 10° elbow may assist to prevent slippage of related to follow-up. A removable splint angulation and 30° malrotation should the immobilisation device on the chubby provides adequate protection while being be applied for those aged ≥10 years forearm (Figure 1B). Acute fractures can easily removed by parents at home after (Table 1).12–14 be managed safely in volar and dorsal a 3–4-week treatment period without Malrotation can be difficult to assess. (sandwich-style) slabs that extend up to further clinical or radiographic follow- As a guide, the radial styloid should face the metacarpophalangeal joints but leave up.6,7 Sports, high impact and loading opposite the bicipital tuberosity of the them free to move. Midshaft and proximal should be avoided for a further four weeks. radius, and the ulnar styloid should face third fractures require immobilisation of opposite the coronoid process of the the elbow joint. Greenstick fractures and ulna.15 The majority of forearm growth Plastic deformity refers to increased plastic deformity occurs at the wrist; therefore, a greater bowing to the radius or ulna without an Greenstick fractures are incomplete degree of angulation can be accepted for obvious fracture line due to multiple fractures involving disruption of 1–3 sides of distal forearm fractures when compared microfractures along the length of the the bone with bending of the others, akin to with more proximal fractures as the deformity.9 Management is similar to bending and splintering a tongue depressor remodelling potential is higher.16 Radial greenstick fractures, and reduction is without snapping it clean in two. Both the and ulnar deviation have less potential indicated on the basis of the degree of radius and ulna are commonly affected, to remodel, and rotational deformities deformity. Follow-up can be simplified as and these fractures commonly occur with have no potential to remodel.14 Clinical for greenstick fractures.17 Plastic deformity falls from a height or during recreational deformity often provides a clue that and isolated greenstick fractures of the activities as a result of combined bending orthopaedic intervention is required. ulna can be associated with radial head and twisting forces.8 A fracture of both Greenstick fractures are inherently dislocation (Monteggia injury), and it is bones at the same level of the forearm unstable and will continue to angulate critical that this is not missed. suggests a bending force was applied, while if not adequately splinted (Figure 1). fractures at different levels suggest that a With an appropriately moulded cast or Complete fractures rotational force has spiralled through both ‘front and backslab’ application, the A complete fracture disrupts the entire bones and the intervening interosseous intact cortex will maintain a degree of cortex, with resultant deformity and membrane.9 Greenstick fractures can affect stability. Aftercare includes one X-ray angulation. These are often found in any region of the forearm, and clinical immediately after cast application if higher-energy injuries, such as falls deformity is common.9,10 fracture manipulation was required, from a height, sports and road traffic Acceptable fracture angulation is that and one follow-up X-ray after 7–10 days accidents.18 Complete fractures may occur which does not require manipulation and to document maintenance of position. in any location and commonly affect is dependent on the capacity to remodel If reduction is maintained, one further both the radius and ulna. The lack of any and restore normal alignment. The most clinic visit at 5–6 weeks post-fracture for cortical continuity allows for complete important determinant is the time until removal of the cast is all that remains.17 displacement as well as shortening, which skeletal maturity, which, as a general X-rays to check union are not required in may appear as ‘bayonet’ deformity on the rule of thumb, occurs at 14 years of age the majority of cases.17 lateral X-ray. Despite complete fracture of for girls and 16 years of age for boys.11 Distal third radius and ulna fractures the bones, the thick periosteal sleeve often Many guidelines stratify angulation for in older children are suitably managed remains intact, providing some stability. Table 1. Acceptable displacement guidelines Fracture type Age <10 years Age ≥10 years Notes Buckle fractures <25° angulation <15° angulation Distal third greenstick or <15° angulation <15° angulation Beware of distal radioulnar joint complete fractures <1 cm shortening <1 cm shortening dislocation Middle and proximal third <15° angulation <10° angulation Beware of radial head dislocations with greenstick or complete fractures <1 cm shortening <1 cm shortening ulnar fractures and plastic deformity Physeal fractures <50% displacement <25% displacement Avoid delayed referrals <30° angulation <25o angulation © The Royal Australian College of General Practitioners 2020 REPRINTED FROM AJGP VOL. 49, NO. 11, NOVEMBER 2020 | 741 CLINICAL A GUIDE TO PAEDIATRIC FOREARM FRACTURES Parents and clinicians alike are often difference in skeletal maturity, girls and dislocation of the distal radioulnar surprised to learn that 100% displacement present on
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