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J Shoulder Elbow Surg (2013) 22, e9-e11

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CASE REPORTS

A rare case of elbow dislocation associatedwith unrecognized fracture of medial epicondyleand delayed ulnar neuropathy in pediatric age

Sara Lima, MDa,*, Jo~ao Freitas Correia, MDa, Rui Pimenta Ribeiro, MDb,Rui Moura Martins, MDa, Nuno Alegrete, MDb, Jorge Coutinho, MDb,Gilberto Melo Costa, MD, PhDb

aCentro Hospitalar Tamega e Sousa, Penafiel, PortugalbCentro Hospitalar S. Jo~ao, Porto, Portugal

Elbow dislocations in children are rare.16,14 They maybe associated with other fractures of this region, with themost common being medial epicondyle avulsion.4 In 15-18% of cases, the fragment is incarcerated within thejoint.2 Less common is the association with paralysis ofthe ulnar nerve, which may result from the injury itself, aswell as from manipulation, such as in closed reduction,or during surgical treatment. Treatment of medial epi-condyle fractures is controversial, with equally satisfac-tory results when comparing conservative treatment andsurgery, even in cases of fractures with deviation.7,10,11

However, open reduction with internal fixation of theepicondyle fragment is clearly indicated in cases of intra-articular entrapment of the fragment, on suspicion ofentrapment of the ulnar nerve or in cases of markedinstability of the elbow.3,5,8,17,18

The authors present the case of a 10-year-old boy witha posterior dislocation of the left elbow, and a fracture ofthe medial epicondyle that was not initially recognizeduntil he developed ulnar nerve palsy 3 months later. Todate, the authors found only 1 case in the English languageliterature involving a detailed description of the history andapproach of this type of injury.9

uests: Sara Lima, MD, Rua das Magn�olias, 59, 4825-102

tugal.

ss: saralimaraujo@gmail.com (S. Lima).

ee front matter � 2013 Journal of Shoulder and Elbow Surgery

/10.1016/j.jse.2012.11.009

Case report

A 10-year-old boy was admitted to the ER following a fall, whichled to a posterior dislocation of the left elbow. It was reduced andneurological examination was normal. The radiological controlconfirmed joint congruency and an associated fracture of themedial epicondyle was not diagnosed (Fig. 1). The patient wastreated conservatively with long arm cast immobilization for 3weeks, followed by physical therapy.

Three months after the fracture, the child developed paresthesia/numbness of the ulnar aspect of the forearm and hand with impair-ment of hand function and finger coordination. On physical exami-nation, the patient presented an incipient claw of the fifth finger,a Wartenberg sign, a positive Tinel sign at the elbow, a positiveFroment test, and an atrophy of the intrinsic muscles of the hand.There was a moderate valgus instability and pain on the medial sideof the elbow as well. The arc of mobility ranged from 5� to 120�.Radiographic examination showed a clear straightening of themedial distal humerus due to the avulsion of the medial epicondyle(Fig. 2). The electromyographic study revealed a left ulnar neurop-athy, with axonotemesis, at the level of the elbow. On the magneticresonance image, the most relevant aspect was the anomalous infe-rior position, apparently due to traction, of the epitrochlear ossifi-cation nucleus, which appears lateral to the olecranon, withconsequent involvement of the insertion of the common flexortendon and collateral ligaments of the ulnar aspect of the elbow.

The patient underwent surgical exploration of the left elbow bya medial approach. Intraoperatively, it was possible to observe scartissue surrounding thenerve at the elbow(Fig. 3) and the intra-articularposition of the ossification nucleus of the medial epicondyle, which

Board of Trustees.

Figure 2 Anteroposterior and lateral radiograph at 3 months offollow-up showsa clear straighteningof themedial distal humerus andanomalous inferior position of the epitrochlear ossification nucleus.

Figure 3 Surgical exploration revealing scar involvement of theulnar nerve.Figure 1 Post-reduction radiograph.

Figure 4 Medial epicondyle and its musculo-ligamentousstructures were identified and released.

Figure 5 Despite the tissue retraction it was possible to reinsertthe medial epicondyle in its bed with a screw.

e10 S. Lima et al.

did not seem to compress the ulnar nerve directly. Decompressionwith subcutaneous anterior transposition of the ulnar nerve was per-formed and the medial epicondyle, with its musculo-ligamentousstructures, was released (Fig. 4) and reinserted into its bed in thedistal humerus with a screw (Fig. 5). The capsuloligamentous struc-tures were repaired and the elbow was immobilized at 90� for about4 weeks, followed by immediate physical therapy.

At the sixth postoperative month, the patient has a stable elbowwith full recovery of the sensory and motor deficits, normalizationof objective findings and a close to normal arc of mobility.

Discussion

Pediatric elbow dislocations are rare, and those associatedwith fracture of the medial epicondyle and delayedneuropathy of the ulnar nerve are even more infrequent. Todate, the authors found only 2 cases reported in the litera-ture of this type of injury,9,14 and only one, where a fractureof the medial epicondyle was not initially diagnosed, issimilar to the case presented.9

The failure to recognize an intra-articular entrapment of theepicondyle can result in a significant restriction ofmobility, aswell as associated with increased risk of injury to the ulnarnerve, which can occur in up to 50% of the cases.3,6

In our case, it is difficult to determine whether the intra-articular position of the fragment resulted from the initial

Complications of elbow dislocation in children e11

injury or subsequent manipulation, and if the ulnarneuropathy was the result of impingement with the frag-ment or secondary involvement due to scarring of the sameinjury. A universal finding when the fragment is incarcer-ated in the joint is a thick fascial band connecting the ulnarnerve to the underlying muscle,1,13 which in this case wasidentified during surgical exploration. It is believed that theconstriction provoked by this band is responsible for theulnar nerve dysfunction. Whatever the cause, a rapidlyprogressive deterioration of nerve function implies animmediate surgical exploration, with anterior transpositionof the nerve.17 The prognosis is much worse the later theintervention. There was a poorer recovery from injury of theulnar nerve in cases in which the intra-articular fragmentremained in this position for a significant period of time.12

Although the surgical treatment of nonunion of theepicondyle fragment is controversial,5,7,15,18 the authorsfound it necessary to reposition it, along with its musculo-ligamentous insertions, in order to reestablish joint stability.

The medial epicondyle fracture associated with elbowdislocation in children may not be easily diagnosed onconventional radiographs because of the small size of thefragment, its ‘‘hidden’’ position behind the distal humerus,and the fact that it can be mistaken for the trochlear ossifi-cation center. However, in the case presented, a closerobservation of the images would have allowed this diagnosis.Not only was the fracture of the medial epicondyle undiag-nosed but its intra-articular position as well. Despite nothaving been an obstacle to closed reduction of the dislocation,its location was probably an obstacle to full extension andflexionof the elbow, as evidencedby thegradual improvementin mobility after the intra-articular removal of the fragment.

Conclusion

Elbow dislocations associated with fractures of themedial epicondyle with intra-articular entrapment can bedifficult to diagnose in the acute phase, and thus a highlevel of suspicion is required. The delayed neuropathy ofthe ulnar nerve appears to be associated with a completerecovery in children, as long as it is promptly treated.

Disclaimer

The authors, their immediate families, and any researchfoundations with which they are affiliated have not

received any financial payments or other benefits fromany commercial entity related to the subject of thisarticle.

References

1. Ashurst APC. An anatomical and surgical study of fractures of the

lower end of the humerus. Philadelphia, PA: Lea & Febiger; 1910.

2. Beaty J, Kasser J. The elbow: physeal fractures, apophyseal injuries of

the distal humerus, osteonecrosis of the trochlea, and t-condylar

fractures. In: Beaty J, Kasser J, editors. Rockwood &Wilkin�s fracturesin children. 6th ed. Philadelphia, PA: Lippincott Williams & Wilkins;

2006. p. 592-660. Chapter 15.

3. Bede WB, Lefebvre AR, Rosman MA. Fractures of the medial

humeral epicondyle in children. Can J Surg 1975;18:137-42.

4. Carlioz H, Abols Y. Posterior dislocation of the elbow in children. J

Ped Othops 1984;4:8-12.

5. Case SL, Hennrikus WL. Surgical treatment of displaced medial

epicondyle fractures in adolescent athletes. Am J Sports Med 1997;25:

682-6.

6. Fairbank HAT, Buxton JD. Displacement of the internal epicondyle

into the elbow joint. Lancet 1934;2:218.

7. Farsetti P, Potenza V, Caterini R, Ippolito E. Long-term results of

treatment of fractures of the medial humeral epicondyle in children. J

Bone Joint Surg Am 2001;83:1299-305.

8. Fowles JV, Slimane N, Kassab MT. Elbow dislocation with avulsion of

the medial epicondyle. J Bone Joint Surg (Br) 1990;72:102-4.

9. Haflah NHM, Ibrahim S, Sapuan J, Abdullah S. An elbow dislocation

in a child with missed medial epicondyle fracture and late ulnar nerve

palsy. J Pediatr Orthop B 2010;19:459-61. http://dx.doi.org/10.1097/

BPB.0b013e32833b6032

10. Hines RF, Herndon WA, Evans JP. Operative treatment of medial

epicondyle fractures in children. Clin Orthop Relat Res 1987;223:

170-4.

11. Kobayashi Y, Oka Y, Ikeda M, Munesada S. Avulsion fracture of the

medial and lateral epicondyles of the humerus. J Shoulder Elbow Surg

2000;9:59-64.

12. Marion J, Faysse R. Fractures de l’epitrochlea. Rev Chir Orthop 1962;

48:447-69.

13. Patrick J. Fracture of the medial epicondyle with displacement into the

elbow joint. J Bone Joint Surg 1946;28:143-7.

14. Rasool MN. Dislocation of the elbow in children. J Bone Joint Surg

(Br) 2004;86-B:1050-8. http://dx.doi.org/10.1302/0301-620X.86B7

15. Schwab GH, Bennett JB, Woods GW, Tullos HS. Biomechanics of

elbow instability: the role of the medial collateral ligament. Clin

Orthop 1980;146:42-52.

16. Stans A, Heirich S. Dislocations of the elbow. In: Beaty J, Kasser J,

editors. Rockwood & Wilkin�s fractures in children. 7th ed.

Philadelphia, PA: Lippincott Williams & Wilkins; 2010. Chapter 16,

p.594-619.

17. Wilson JN. The treatment of fractures of the medial epicondyle of the

humerus. J Bone Joint Surg (Br) 1960;42:778-81.

18. Woods GW, Tullos HS. Elbow instability and medial epicondyle

fractures. Am J Sports Med 1977;5:23-30.