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Incarcerated Medial Epicondyle Fracture Following Pediatric Elbow Dislocation: 11 Cases
SCIENTIFIC ARTICLE
Incarcerated Medial Epicondyle Fracture Following Pediatric Elbow Dislocation: 11 Cases Seth D. Dodds, MD, Brody A. Flanagin, MD, Daniel D. Bohl, MPH, Peter A. DeLuca, MD, Brian G. Smith, MD
Purpose To describe outcomes after surgical management of pediatric elbow dislocation with incarceration of the medial epicondyle. Methods We conducted a retrospective case review of 11 consecutive children and adolescents with an incarcerated medial epicondyle fracture after elbow dislocation. All patients underwent open reduction internal fixation using a similar technique. We characterized outcomes at final follow-up. Results Average follow-up was 14 months (range, 4e56 mo). All patients had clinical and radiographic signs of healing at final follow-up. There was no radiographic evidence of loss of reduction at intervals or at final follow-up. There were no cases of residual deformity or valgus instability. Average final arc of elbow motion was 4 to 140 . All patients had forearm rotation from 90 supination to 90 pronation. Average Mayo elbow score was 99.5. Four of 11 patients had ulnar nerve symptoms postoperatively and 1 required a second operation for ulnar nerve symptoms. In addition, 1 required a second operation for flexion contracture release with excision of heterotopic ossification. Three patients had ulnar nerve symptoms at final followup. Two of these had mild paresthesia only and 1 had both mild paresthesia and weakness. Conclusions Our results suggest that open reduction internal fixation of incarcerated medial epicondyle fractures after elbow dislocation leads to satisfactory motion and function; however, the injury carries a high risk for complications, particularly ulnar neuropathy. (J Hand Surg Am. 2014;39(9):1739e1745. Copyright Ó 2014 by the American Society for Surgery of the Hand. All rights reserved.) Type of study/level of evidence Therapeutic IV. Key words Incarcerated medial epicondyle fracture, elbow dislocation, pediatric, open reduction internal fixation.
D
in 3% to 6% of pediatric elbow injuries, with a peak incidence in the second decade of life.1e5 Elbow dislocation leads to tension on the ulnar collateral ISLOCATION OF THE ELBOW OCCURS
From the Department of Orthopaedics and Rehabilitation, Yale School of Medicine, New Haven; and Connecticut Orthopaedic Specialists, Hamden, CT. Received for publication January 23, 2014; accepted in revised form June 12, 2014. No benefits in any form have been received or will be received related directly or indirectly to the subject of this article. Corresponding author: Seth D. Dodds, MD, Department of Orthopaedics and Rehabilitation, Yale School of Medicine, 800 Howard Avenue, New Haven, CT 06510; e-mail: [email protected]. 0363-5023/14/3909-0012$36.00/0 http://dx.doi.org/10.1016/j.jhsa.2014.06.012
ligament, which originates at the medial epicondyle. The medial epicondyle is the last ossification center to fuse to the distal humerus, typically between ages 15 and 20 years.2,6 As a result, the most common fracture associated with pediatric elbow dislocation is an avulsion fracture of the medial epicondyle.4 In 15% to 25% of pediatric elbow dislocations with concurrent fracture of the medial epicondyle, the medial epicondyle becomes incarcerated in the ulnohumeral joint.6,7 This is a potentially devastating phenomenon if unrecognized, with potential chronic complications including pain, limitation of movement, elbow instability, and ulnar nerve paresthesias and paresis. Key clinical findings include a block to motion (especially extension) after reduction or simply the inability to
Ó 2014 ASSH
r
Published by Elsevier, Inc. All rights reserved.
r
1739
1740
INCARCERATED MEDIAL EPICONDYLE
TABLE 1.
Patient Characteristics and Outcomes Index Procedure Preoperative Ulnar Neuropraxia
Time to Surgery, d
Closed
No
10
No
Closed
Yes
R
Yes
Spontaneous
F
R
Yes
15
M
L
6
11
F
7
12
8
Sex
Side of Injury
Injury on Dominant Side
10
F
R
Yes
2
12
F
L
3
12
M
4
9
5
Patient
Age, y
1
Reduction of Elbow Dislocation
Instrumentation
External Ulnar Neurolysis
One 3.5-mm cannulated screw
No
0
Two 2.7-mm cortical screws
Yes
Yes
0
Two 2.7-mm cortical screws
Yes
Spontaneous
Yes
1
One 2.4-mm cortical screw One 2.0-mm cortical screw
Yes
No
Spontaneous
No
0
Two 4.0-mm cannulated screws
No
R
No
Closed
No
0
One 4.0-mm cannulated screw
No
M
L
No
Open (during index procedure)
No
0
One 3.5-mm cannulated screw
No
12
M
R
Yes
Spontaneous
Yes
4
One 4.0-mm cannulated screw
Yes
9
13
M
R
Yes
Spontaneous
Yes
1
One 4.0-mm cannulated screw
Yes
10
11
F
L
No
Closed
Yes
0
Two 4.0-mm cannulated screws
No
11
12
F
R
Yes
Closed
No
0
One 3.5-mm cannulated screw
No
HO, heterotopic ossification.
fully reduce.7 Reduction can occur spontaneously, which adds to the challenge of diagnosing an incarcerated medial epicondyle fragment. On a plain radiograph, any time the medial epicondyle fragment appears at the level of the joint, it should be considered to be at least partially incarcerated until proven otherwise.8 The presence of an incarcerated fragment represents an absolute indication for urgent operative repair.6e9 Operative removal of the fracture fragment under direct visualization followed by anatomic reduction internal fixation restores elbow anatomy and allows for early postoperative motion to reduce the risk of stiffness. Surgical interventions include suture repair, Kirschner wire fixation, screw fixation, and excision of the medial epicondyle with suturing of the soft tissue to the periosteum.6 In patients with preoperative ulnar nerve dysfunction, operative treatment also allows for exploration of the ulnar nerve. J Hand Surg Am.
r
Outcomes after management of medial epicondyle fractures in cases without incarceration of the medial epicondyle have been well described.10,11 Here, we present a series of 11 consecutive cases of surgically managed pediatric elbow dislocation with incarceration of the medial epicondyle. We aimed to characterize motion, functional outcome, ulnar nerve dysfunction, heterotopic ossification, and any other complications. MATERIALS AND METHODS After we obtained institutional review board approval, we identified 11 consecutive patients who were surgically treated between September 2006 and November 2010 for incarceration of the medial epicondyle after elbow dislocation (Table 1). Patients’ average age was 12 years (range, 9e15 y). Six were girls and 5 were boys. All patients sustained a fall onto the affected extremity. In all cases, incarceration of the Vol. 39, September 2014
1741
INCARCERATED MEDIAL EPICONDYLE
TABLE 1.
(Continued) Final Follow-Up
Additional Procedures
Flexion contracture release and excision of HO at 6 mo
Removal of hardware, ulnar neurolysis, and ulnar transposition at 2 mo
Elbow Position (degrees)
Forearm Rotation (degrees)
Follow-Up, mo
Extension
Flexion
Pronation
Supination
Mayo Elbow Score
4
10
135
90
90
100
Mild lateral HO
13
15
140
90
90
100
Mild lateral HO
4
5
145
90
90
100
Mild lateral HO
7
0
150
90
90
100
Mild ulnar paresthesia
5
0
150
90
90
100
Mild ulnar paresthesia and weakness
8
0
150
90
90
100
34
5
140
90
90
100
7
5
150
90
90
100
7
0
150
90
90
100
10
5
105
90
90
95
56
0
125
90
90
100
medial epicondyle fragment was diagnosed using plain elbow posteroanterior, lateral, and oblique radiographs. The dominant elbow was affected in 6 cases. All injuries were closed and there were no other associated fractures. Five patients presented with the medial epicondyle entrapped in the ulnohumeral joint after spontaneous reduction of a presumed elbow dislocation, 5 had an entrapped medial epicondyle after undergoing closed reduction under conscious sedation for an associated posterolateral elbow dislocation (Fig. 1), and 1 presented with an irreducible posterolateral fracture dislocation of the elbow with intra-articular incarceration of the medial epicondyle necessitating open treatment of both injuries. All patients underwent open reduction internal fixation of the medial epicondyle fracture. Average time between injury and surgery was 2 days (range, 0e10 d). In all cases, a medial approach to the elbow J Hand Surg Am.
r
Complications at Final Follow-Up
Mild ulnar paresthesia
through an incision centered just posterior to the medial epicondyle was performed. The ulnar nerve was identified and protected in all cases. After the fracture fragment was retrieved from the elbow joint, the fracture was anatomically reduced and stabilized with 1 or 2 cannulated or cortical screws (Fig. 2). We observed some degree of articular destruction in all cases, ranging from contusion of the articular cartilage to full-thickness articular gouges in the cartilage caused by the incarcerated fracture fragment. Six patients had preoperative ulnar symptoms, 5 of whom underwent external neurolysis. After external neurolysis and fracture repair, ulnar nerves were examined in their typical posteromedial location for subluxation and the potential for irritation from the internal fixation. No nerve was found to be unstable or too close to the hardware. The ulnar nerve was not transposed during the index procedure in any case. Elbows were Vol. 39, September 2014
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INCARCERATED MEDIAL EPICONDYLE
FIGURE 1: A, B Representative prereduction radiographs (patient 6) showing a displaced medial epicondyle fracture in association with a posterolateral elbow dislocation. C, D Representative postreduction radiographs (patient 1) showing intra-articular incarceration of the fracture fragment within the ulnohumeral joint.
FIGURE 2: A, B Representative postoperative radiographs (patient 4) showing reduction and fixation of the medial epicondyle fracture with 2 cortical screws.
fabricated in an orthosis for an average of 11 days (range, 5e21 d), after which patients were instructed to initiate active range of motion exercises. Ten patients (all but patient 5) received physical therapy. Indomethacin was not used as prophylaxis for heterotopic ossification in any patient. J Hand Surg Am.
r
At postoperative visits, we conducted complete history and physical examinations as part of routine practice. In particular, patients were evaluated for ulnar neuropathy and characterized at the time of chart review as having mild paresthesias (intermittent numbness or tingling), severe paresthesias (constant numbness or Vol. 39, September 2014
INCARCERATED MEDIAL EPICONDYLE
tingling), and/or motor weakness. Two-point discrimination was not routinely performed. The Mayo elbow score was calculated based on a combination of questions answered by either the parent or the patient (as was age appropriate) and clinical examination for range of motion and stability.12 Previous studies have used the Mayo elbow for children and adolescents.13,14 RESULTS Average postoperative follow-up was 14 months (range, 4e56 mo). All patients had clinical and radiographic signs of healing at final follow-up. There was no radiographic evidence of loss of reduction at interval or final follow-up. In addition, by examination there were no cases of residual deformity or valgus instability. Average arc of elbow motion was from 4 to 140 (Table 1). All patients had forearm rotation from 90 supination to 90 pronation. Average Mayo elbow score was 99.5. Four patients had postoperative ulnar nerve palsies and 3 had ulnar nerve palsies at final follow-up (Table 1). Three of 5 patients who underwent external neurolysis for preoperative ulnar nerve symptoms experienced complete recovery at final follow-up. The other 2 patients had mild paresthesias that did not warrant reoperation. The patient who had preoperative ulnar symptoms but did not undergo ulnar nerve neurolysis in the index procedure (patient 10) required a return to the operating room 2 months later for hardware removal and ulnar nerve neurolysis anterior transposition; this patient had no ulnar nerve symptoms at final follow-up (10 mo). One patient without preoperative ulnar nerve symptoms developed postoperative ulnar nerve palsy (patient 5). At final follow-up (5 mo), this patient had intermittent residual numbness and tingling in the little and ring fingers and slight motor weakness of the little and ring fingers. The symptoms were mild enough that the treating surgeon and family did not wish to pursue further intervention. Four patients developed heterotopic ossification around the elbow joint (Table 1). Three of these did not require additional surgery and had full range of forearm rotation, elbow extension ranging from 5 to 15 , and elbow flexion ranging from 135 to 145 at final follow-up. One patient required release of a flexion contracture release with excision of heterotopic ossification at 6 months. At final follow-up (34 mo), this patient had full range of forearm rotation and extension-flexion of 5 and 140 , respectively. DISCUSSION In 15% to 25% of pediatric elbow dislocations with concurrent fracture of the medial epicondyle, the J Hand Surg Am.
r
1743
medial epicondyle fragment becomes incarcerated in the ulnohumeral joint.6,7 Outcomes after surgical management of medial epicondyle fractures in cases without incarceration of the medial epicondyle have been well described.10,11 Our results in 11 patients with entrapment of the medial epicondyle demonstrated satisfactory clinical outcomes as measured by range of motion and Mayo elbow score. Operative management of incarcerated medial epicondyle fractures allows for removal of the offending fragment under direct visualization followed by anatomic reduction internal fixation. For a medial epicondyle fracture to become entrapped within the ulnohumeral joint, an elbow dislocation must have occurred, which indicates substantial associated ligamentous disruption. Given the magnitude of this injury, operative reduction and stabilization of the flexor-pronator muscle origin and medial collateral ligament origin may offer critical protection against valgus instability and allow for early elbow motion, which may explain our overall favorable results in terms of valgus stability, range of motion, and function. We observed a reoperation rate of 18%, likely explained by the severity of this type of fracturedislocation with a persistently incarcerated bone fragment causing articular destruction and ulnar nerve injury. One of 11 patients in our study required a second operation for persistent ulnar nerve symptoms and 1 underwent flexion contracture release with excision of heterotopic ossification. Three of 11 had mild residual ulnar nerve symptoms at final follow-up. Our rate of ulnar nerve palsy can be compared with a population of patients identified in a meta-analysis who were treated for medial epicondyle fractures that were not necessarily incarcerated.11 That study reported on the 2 types together and found that 5% of patients who were operatively treated had ulnar nerve symptoms at final followup—a much lower proportion than the 27% observed in our study. Also in our study, 6 of 11 patients (55%) had ulnar nerve symptoms preoperatively, whereas in the meta-analysis of patients with fractures that were not necessarily incarcerated, 11% who were operatively treated had preoperative ulnar nerve symptoms. Unfortunately, the meta-analysis did not differentiate patients who did and did not have elbow dislocation concurrent with the medial epicondyle fracture. Hence, what would be a more specific comparison between the data from the meta-analysis and ours cannot be conducted. Injury of the ulnar or median nerve occurs initially in about 10% of elbow dislocations overall but resolves spontaneously within Vol. 39, September 2014
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INCARCERATED MEDIAL EPICONDYLE
3 months in the vast majority of cases.4 Hence, our data suggest that incarceration of the medial epicondyle after elbow dislocation is associated with rates of mild but persistent ulnar neuropathy several times greater than those observed after simple elbow dislocation. Because the rates of ulnar neuropathy in our study were high both preoperatively and at final follow-up, the damage to the nerve is less likely to occur from iatrogenic injury and more likely to be the direct result of the initial trauma. Heterotopic ossification occurred in 4 of 11 patients. Although indomethacin treatment has been used to decrease the development of heterotopic ossification about the acutely injured elbow, indomethacin is not a benign medication; it is associated with gastric irritation and even bleeding as concerning side effects. We have chosen not to use this medication in children. Instead, we currently initiate early range of motion within 7 to 10 days of surgical treatment. Time to treatment of incarcerated medial epicondyle fractures may affect outcomes. Although the average time to treatment was 2 days in our series, one patient experienced a delay of 10 days until operative repair owing to a missed diagnosis (because the entrapped medial epicondyle was not appreciated on postreduction films). This patient ultimately had elbow motion limited to extension-flexion of 110 to 135 . When there is no obvious elbow dislocation upon initial presentation, findings associated with an incarcerated medial epicondyle fracture can be subtle and easily overlooked.7 This challenge highlights the need for careful clinical and radiographic examination of the child or adolescent with an acute elbow injury to avoid a delay in diagnosis. As demonstrated in our particular patient, a delay in operative treatment may compromise functional outcome after these injuries. We used screws in all cases for fracture fixation. Screws at the posteromedial elbow, especially at the medial epicondyle, can be prominent. However, we bury them as much as possible and have found that adolescents seldom want to undergo a second procedure for removal of this hardware. Our study had several limitations. First, all retrospective case series carry an inherently lower level of evidence compared with other study designs. Second, our sample size was small, with 11 patients. Finally, 3 patients’ follow-ups were less than 6 months. Two of these had mild heterotopic ossification that could have become more pronounced with time and 1 had persistent ulnar nerve symptoms. This was a retrospective case series conducted among the clinical practices of several surgeons, and several patients
J Hand Surg Am.
r
simply did not return to clinic for follow-up as prescribed. Nevertheless, we thought it was important to report on those patients with lesser follow-up because there is information to be gleaned even from their findings, particularly in light of the limited literature on this topic. Outcomes may have changed if the patients had been observed for longer. We advise physicians to review radiographs after elbow dislocation for incarcerated fragments and to examine patients carefully for ulnar neuropathy preoperatively. In cases in which one cannot be certain whether there is an incarcerated fragment after closed reduction of an elbow dislocation, we recommend obtaining a computed tomographic or magnetic resonance imaging study for clarification. If postreduction radiographs were taken through plaster, removal of plaster and re-imaging would likely improve fragment visualization. We recommend exploration of the ulnar nerve only in patients with preoperative nerve palsy. We recommend release of the ulnar nerve if there are ulnar nerve symptoms preoperatively, if the nerve is contused, or if the nerve itself is entrapped in the joint along with the medial epicondyle fracture fragment. This was our practice before the study, and the study results support this practice in that they document a high rate of ulnar nerve palsy for which all possible corrective measures should be undertaken when the ulnar nerve is at risk. Moreover, we recommend identifying and protecting the ulnar nerve in all cases of medial epicondyle fracture open reduction internal fixation in an effort to minimize risk to this critical motor and sensory nerve. Delays in treatment may result in poorer outcomes, specifically with respect to range of motion; hence, we advise exercising extreme caution in ruling out incarceration on presentation to minimize time to operative reduction. Surgeons should advise patients’ families that persistent ulnar neuropathy and heterotopic ossification are common occurrences after this combination of injuries. REFERENCES 1. Carlioz H, Abols Y. Posterior dislocation of the elbow in children. J Pediatr Orthop. 1984;4(1):8e12. 2. Wilkins KE. Fractures and dislocations of the elbow region. In: Rockwood CA, Wilkins KE, King RE, eds. Fractures in Children. 4th ed. Vol. 3. Philadelphia, PA: Lippincott-Raven; 1996:653e887. 3. Rasool MN. Dislocations of the elbow in children. J Bone Joint Surg Br. 2004;86(7):1050e1058. 4. Price CT, Flynn JM. Management of fractures. In: Morrissy RT, Weinstein SL, eds. Lovell & Winter’s Pediatric Orthopaedics. 6th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2006: 1430e1516.
Vol. 39, September 2014
INCARCERATED MEDIAL EPICONDYLE
5. Fowles JV, Slimane N, Kassab MT. Elbow dislocation with avulsion of the medial humeral epicondyle. J Bone Joint Surg Br. 1990;72(1): 102e104. 6. Gottschalk HP, Eisner E, Hosalkar HS. Medial epicondyle fractures in the pediatric population. J Am Acad Orthop Surg. 2012;20(4): 223e232. 7. Beaty JH, Kasser JR. The elbow: physeal fractures, apophyseal injuries of the distal humerus, osteonecrosis of the trochlea, and T-condylar fractures. In: Beaty JH, Kasser JR, eds. Rockwood and Wilkins’ Fractures in Children. 7th ed. Philadelphia, PA: Lippincott, Williams & Wilkins; 2010:566e887. 8. Patrick J. Fracture of the medial epicondyle with displacement into the elbow-joint. J Bone Joint Surg Am. 1946;28:143e147. 9. Roberts NW. Displacement of the internal epicondyle into the elbow joint. Lancet. 1934;224(5785):78e79.
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10. 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(9):1299e1305. 11. Kamath AF, Baldwin K, Horneff J, Hosalkar HS. Operative versus non-operative management of pediatric medial epicondyle fractures: a systematic review. J Child Orthop. 2009;3(5):345e357. 12. Morrey BF, An KN, Chao EYS. Functional evaluation of the elbow. In: Morrey BF, ed. The Elbow and Its Disorders. Philadelphia, PA: WB Saunders; 1993:86e89. 13. Moraleda L, Valencia M, Barco R, González-Moran G. Natural history of unreduced Gartland type-II supracondylar fractures of the humerus in children: a two to thirteen-year follow-up study. J Bone Joint Surg Am. 2013;95(1):28e34. 14. Bowakim J, Marti R, Curto A. Elbow septic arthritis in children: clinical presentation and management. J Pediatr Orthop B. 2010;19(3):281e284.
Vol. 39, September 2014
Incarcerated Medial Epicondyle Fracture Following Pediatric Elbow Dislocation: 11 Cases Seth D. Dodds, MD, Brody A. Flanagin, MD, Daniel D. Bohl, MPH, Peter A. DeLuca, MD, Brian G. Smith, MD
Purpose To describe outcomes after surgical management of pediatric elbow dislocation with incarceration of the medial epicondyle. Methods We conducted a retrospective case review of 11 consecutive children and adolescents with an incarcerated medial epicondyle fracture after elbow dislocation. All patients underwent open reduction internal fixation using a similar technique. We characterized outcomes at final follow-up. Results Average follow-up was 14 months (range, 4e56 mo). All patients had clinical and radiographic signs of healing at final follow-up. There was no radiographic evidence of loss of reduction at intervals or at final follow-up. There were no cases of residual deformity or valgus instability. Average final arc of elbow motion was 4 to 140 . All patients had forearm rotation from 90 supination to 90 pronation. Average Mayo elbow score was 99.5. Four of 11 patients had ulnar nerve symptoms postoperatively and 1 required a second operation for ulnar nerve symptoms. In addition, 1 required a second operation for flexion contracture release with excision of heterotopic ossification. Three patients had ulnar nerve symptoms at final followup. Two of these had mild paresthesia only and 1 had both mild paresthesia and weakness. Conclusions Our results suggest that open reduction internal fixation of incarcerated medial epicondyle fractures after elbow dislocation leads to satisfactory motion and function; however, the injury carries a high risk for complications, particularly ulnar neuropathy. (J Hand Surg Am. 2014;39(9):1739e1745. Copyright Ó 2014 by the American Society for Surgery of the Hand. All rights reserved.) Type of study/level of evidence Therapeutic IV. Key words Incarcerated medial epicondyle fracture, elbow dislocation, pediatric, open reduction internal fixation.
D
in 3% to 6% of pediatric elbow injuries, with a peak incidence in the second decade of life.1e5 Elbow dislocation leads to tension on the ulnar collateral ISLOCATION OF THE ELBOW OCCURS
From the Department of Orthopaedics and Rehabilitation, Yale School of Medicine, New Haven; and Connecticut Orthopaedic Specialists, Hamden, CT. Received for publication January 23, 2014; accepted in revised form June 12, 2014. No benefits in any form have been received or will be received related directly or indirectly to the subject of this article. Corresponding author: Seth D. Dodds, MD, Department of Orthopaedics and Rehabilitation, Yale School of Medicine, 800 Howard Avenue, New Haven, CT 06510; e-mail: [email protected]. 0363-5023/14/3909-0012$36.00/0 http://dx.doi.org/10.1016/j.jhsa.2014.06.012
ligament, which originates at the medial epicondyle. The medial epicondyle is the last ossification center to fuse to the distal humerus, typically between ages 15 and 20 years.2,6 As a result, the most common fracture associated with pediatric elbow dislocation is an avulsion fracture of the medial epicondyle.4 In 15% to 25% of pediatric elbow dislocations with concurrent fracture of the medial epicondyle, the medial epicondyle becomes incarcerated in the ulnohumeral joint.6,7 This is a potentially devastating phenomenon if unrecognized, with potential chronic complications including pain, limitation of movement, elbow instability, and ulnar nerve paresthesias and paresis. Key clinical findings include a block to motion (especially extension) after reduction or simply the inability to
Ó 2014 ASSH
r
Published by Elsevier, Inc. All rights reserved.
r
1739
1740
INCARCERATED MEDIAL EPICONDYLE
TABLE 1.
Patient Characteristics and Outcomes Index Procedure Preoperative Ulnar Neuropraxia
Time to Surgery, d
Closed
No
10
No
Closed
Yes
R
Yes
Spontaneous
F
R
Yes
15
M
L
6
11
F
7
12
8
Sex
Side of Injury
Injury on Dominant Side
10
F
R
Yes
2
12
F
L
3
12
M
4
9
5
Patient
Age, y
1
Reduction of Elbow Dislocation
Instrumentation
External Ulnar Neurolysis
One 3.5-mm cannulated screw
No
0
Two 2.7-mm cortical screws
Yes
Yes
0
Two 2.7-mm cortical screws
Yes
Spontaneous
Yes
1
One 2.4-mm cortical screw One 2.0-mm cortical screw
Yes
No
Spontaneous
No
0
Two 4.0-mm cannulated screws
No
R
No
Closed
No
0
One 4.0-mm cannulated screw
No
M
L
No
Open (during index procedure)
No
0
One 3.5-mm cannulated screw
No
12
M
R
Yes
Spontaneous
Yes
4
One 4.0-mm cannulated screw
Yes
9
13
M
R
Yes
Spontaneous
Yes
1
One 4.0-mm cannulated screw
Yes
10
11
F
L
No
Closed
Yes
0
Two 4.0-mm cannulated screws
No
11
12
F
R
Yes
Closed
No
0
One 3.5-mm cannulated screw
No
HO, heterotopic ossification.
fully reduce.7 Reduction can occur spontaneously, which adds to the challenge of diagnosing an incarcerated medial epicondyle fragment. On a plain radiograph, any time the medial epicondyle fragment appears at the level of the joint, it should be considered to be at least partially incarcerated until proven otherwise.8 The presence of an incarcerated fragment represents an absolute indication for urgent operative repair.6e9 Operative removal of the fracture fragment under direct visualization followed by anatomic reduction internal fixation restores elbow anatomy and allows for early postoperative motion to reduce the risk of stiffness. Surgical interventions include suture repair, Kirschner wire fixation, screw fixation, and excision of the medial epicondyle with suturing of the soft tissue to the periosteum.6 In patients with preoperative ulnar nerve dysfunction, operative treatment also allows for exploration of the ulnar nerve. J Hand Surg Am.
r
Outcomes after management of medial epicondyle fractures in cases without incarceration of the medial epicondyle have been well described.10,11 Here, we present a series of 11 consecutive cases of surgically managed pediatric elbow dislocation with incarceration of the medial epicondyle. We aimed to characterize motion, functional outcome, ulnar nerve dysfunction, heterotopic ossification, and any other complications. MATERIALS AND METHODS After we obtained institutional review board approval, we identified 11 consecutive patients who were surgically treated between September 2006 and November 2010 for incarceration of the medial epicondyle after elbow dislocation (Table 1). Patients’ average age was 12 years (range, 9e15 y). Six were girls and 5 were boys. All patients sustained a fall onto the affected extremity. In all cases, incarceration of the Vol. 39, September 2014
1741
INCARCERATED MEDIAL EPICONDYLE
TABLE 1.
(Continued) Final Follow-Up
Additional Procedures
Flexion contracture release and excision of HO at 6 mo
Removal of hardware, ulnar neurolysis, and ulnar transposition at 2 mo
Elbow Position (degrees)
Forearm Rotation (degrees)
Follow-Up, mo
Extension
Flexion
Pronation
Supination
Mayo Elbow Score
4
10
135
90
90
100
Mild lateral HO
13
15
140
90
90
100
Mild lateral HO
4
5
145
90
90
100
Mild lateral HO
7
0
150
90
90
100
Mild ulnar paresthesia
5
0
150
90
90
100
Mild ulnar paresthesia and weakness
8
0
150
90
90
100
34
5
140
90
90
100
7
5
150
90
90
100
7
0
150
90
90
100
10
5
105
90
90
95
56
0
125
90
90
100
medial epicondyle fragment was diagnosed using plain elbow posteroanterior, lateral, and oblique radiographs. The dominant elbow was affected in 6 cases. All injuries were closed and there were no other associated fractures. Five patients presented with the medial epicondyle entrapped in the ulnohumeral joint after spontaneous reduction of a presumed elbow dislocation, 5 had an entrapped medial epicondyle after undergoing closed reduction under conscious sedation for an associated posterolateral elbow dislocation (Fig. 1), and 1 presented with an irreducible posterolateral fracture dislocation of the elbow with intra-articular incarceration of the medial epicondyle necessitating open treatment of both injuries. All patients underwent open reduction internal fixation of the medial epicondyle fracture. Average time between injury and surgery was 2 days (range, 0e10 d). In all cases, a medial approach to the elbow J Hand Surg Am.
r
Complications at Final Follow-Up
Mild ulnar paresthesia
through an incision centered just posterior to the medial epicondyle was performed. The ulnar nerve was identified and protected in all cases. After the fracture fragment was retrieved from the elbow joint, the fracture was anatomically reduced and stabilized with 1 or 2 cannulated or cortical screws (Fig. 2). We observed some degree of articular destruction in all cases, ranging from contusion of the articular cartilage to full-thickness articular gouges in the cartilage caused by the incarcerated fracture fragment. Six patients had preoperative ulnar symptoms, 5 of whom underwent external neurolysis. After external neurolysis and fracture repair, ulnar nerves were examined in their typical posteromedial location for subluxation and the potential for irritation from the internal fixation. No nerve was found to be unstable or too close to the hardware. The ulnar nerve was not transposed during the index procedure in any case. Elbows were Vol. 39, September 2014
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INCARCERATED MEDIAL EPICONDYLE
FIGURE 1: A, B Representative prereduction radiographs (patient 6) showing a displaced medial epicondyle fracture in association with a posterolateral elbow dislocation. C, D Representative postreduction radiographs (patient 1) showing intra-articular incarceration of the fracture fragment within the ulnohumeral joint.
FIGURE 2: A, B Representative postoperative radiographs (patient 4) showing reduction and fixation of the medial epicondyle fracture with 2 cortical screws.
fabricated in an orthosis for an average of 11 days (range, 5e21 d), after which patients were instructed to initiate active range of motion exercises. Ten patients (all but patient 5) received physical therapy. Indomethacin was not used as prophylaxis for heterotopic ossification in any patient. J Hand Surg Am.
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At postoperative visits, we conducted complete history and physical examinations as part of routine practice. In particular, patients were evaluated for ulnar neuropathy and characterized at the time of chart review as having mild paresthesias (intermittent numbness or tingling), severe paresthesias (constant numbness or Vol. 39, September 2014
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tingling), and/or motor weakness. Two-point discrimination was not routinely performed. The Mayo elbow score was calculated based on a combination of questions answered by either the parent or the patient (as was age appropriate) and clinical examination for range of motion and stability.12 Previous studies have used the Mayo elbow for children and adolescents.13,14 RESULTS Average postoperative follow-up was 14 months (range, 4e56 mo). All patients had clinical and radiographic signs of healing at final follow-up. There was no radiographic evidence of loss of reduction at interval or final follow-up. In addition, by examination there were no cases of residual deformity or valgus instability. Average arc of elbow motion was from 4 to 140 (Table 1). All patients had forearm rotation from 90 supination to 90 pronation. Average Mayo elbow score was 99.5. Four patients had postoperative ulnar nerve palsies and 3 had ulnar nerve palsies at final follow-up (Table 1). Three of 5 patients who underwent external neurolysis for preoperative ulnar nerve symptoms experienced complete recovery at final follow-up. The other 2 patients had mild paresthesias that did not warrant reoperation. The patient who had preoperative ulnar symptoms but did not undergo ulnar nerve neurolysis in the index procedure (patient 10) required a return to the operating room 2 months later for hardware removal and ulnar nerve neurolysis anterior transposition; this patient had no ulnar nerve symptoms at final follow-up (10 mo). One patient without preoperative ulnar nerve symptoms developed postoperative ulnar nerve palsy (patient 5). At final follow-up (5 mo), this patient had intermittent residual numbness and tingling in the little and ring fingers and slight motor weakness of the little and ring fingers. The symptoms were mild enough that the treating surgeon and family did not wish to pursue further intervention. Four patients developed heterotopic ossification around the elbow joint (Table 1). Three of these did not require additional surgery and had full range of forearm rotation, elbow extension ranging from 5 to 15 , and elbow flexion ranging from 135 to 145 at final follow-up. One patient required release of a flexion contracture release with excision of heterotopic ossification at 6 months. At final follow-up (34 mo), this patient had full range of forearm rotation and extension-flexion of 5 and 140 , respectively. DISCUSSION In 15% to 25% of pediatric elbow dislocations with concurrent fracture of the medial epicondyle, the J Hand Surg Am.
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medial epicondyle fragment becomes incarcerated in the ulnohumeral joint.6,7 Outcomes after surgical management of medial epicondyle fractures in cases without incarceration of the medial epicondyle have been well described.10,11 Our results in 11 patients with entrapment of the medial epicondyle demonstrated satisfactory clinical outcomes as measured by range of motion and Mayo elbow score. Operative management of incarcerated medial epicondyle fractures allows for removal of the offending fragment under direct visualization followed by anatomic reduction internal fixation. For a medial epicondyle fracture to become entrapped within the ulnohumeral joint, an elbow dislocation must have occurred, which indicates substantial associated ligamentous disruption. Given the magnitude of this injury, operative reduction and stabilization of the flexor-pronator muscle origin and medial collateral ligament origin may offer critical protection against valgus instability and allow for early elbow motion, which may explain our overall favorable results in terms of valgus stability, range of motion, and function. We observed a reoperation rate of 18%, likely explained by the severity of this type of fracturedislocation with a persistently incarcerated bone fragment causing articular destruction and ulnar nerve injury. One of 11 patients in our study required a second operation for persistent ulnar nerve symptoms and 1 underwent flexion contracture release with excision of heterotopic ossification. Three of 11 had mild residual ulnar nerve symptoms at final follow-up. Our rate of ulnar nerve palsy can be compared with a population of patients identified in a meta-analysis who were treated for medial epicondyle fractures that were not necessarily incarcerated.11 That study reported on the 2 types together and found that 5% of patients who were operatively treated had ulnar nerve symptoms at final followup—a much lower proportion than the 27% observed in our study. Also in our study, 6 of 11 patients (55%) had ulnar nerve symptoms preoperatively, whereas in the meta-analysis of patients with fractures that were not necessarily incarcerated, 11% who were operatively treated had preoperative ulnar nerve symptoms. Unfortunately, the meta-analysis did not differentiate patients who did and did not have elbow dislocation concurrent with the medial epicondyle fracture. Hence, what would be a more specific comparison between the data from the meta-analysis and ours cannot be conducted. Injury of the ulnar or median nerve occurs initially in about 10% of elbow dislocations overall but resolves spontaneously within Vol. 39, September 2014
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3 months in the vast majority of cases.4 Hence, our data suggest that incarceration of the medial epicondyle after elbow dislocation is associated with rates of mild but persistent ulnar neuropathy several times greater than those observed after simple elbow dislocation. Because the rates of ulnar neuropathy in our study were high both preoperatively and at final follow-up, the damage to the nerve is less likely to occur from iatrogenic injury and more likely to be the direct result of the initial trauma. Heterotopic ossification occurred in 4 of 11 patients. Although indomethacin treatment has been used to decrease the development of heterotopic ossification about the acutely injured elbow, indomethacin is not a benign medication; it is associated with gastric irritation and even bleeding as concerning side effects. We have chosen not to use this medication in children. Instead, we currently initiate early range of motion within 7 to 10 days of surgical treatment. Time to treatment of incarcerated medial epicondyle fractures may affect outcomes. Although the average time to treatment was 2 days in our series, one patient experienced a delay of 10 days until operative repair owing to a missed diagnosis (because the entrapped medial epicondyle was not appreciated on postreduction films). This patient ultimately had elbow motion limited to extension-flexion of 110 to 135 . When there is no obvious elbow dislocation upon initial presentation, findings associated with an incarcerated medial epicondyle fracture can be subtle and easily overlooked.7 This challenge highlights the need for careful clinical and radiographic examination of the child or adolescent with an acute elbow injury to avoid a delay in diagnosis. As demonstrated in our particular patient, a delay in operative treatment may compromise functional outcome after these injuries. We used screws in all cases for fracture fixation. Screws at the posteromedial elbow, especially at the medial epicondyle, can be prominent. However, we bury them as much as possible and have found that adolescents seldom want to undergo a second procedure for removal of this hardware. Our study had several limitations. First, all retrospective case series carry an inherently lower level of evidence compared with other study designs. Second, our sample size was small, with 11 patients. Finally, 3 patients’ follow-ups were less than 6 months. Two of these had mild heterotopic ossification that could have become more pronounced with time and 1 had persistent ulnar nerve symptoms. This was a retrospective case series conducted among the clinical practices of several surgeons, and several patients
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simply did not return to clinic for follow-up as prescribed. Nevertheless, we thought it was important to report on those patients with lesser follow-up because there is information to be gleaned even from their findings, particularly in light of the limited literature on this topic. Outcomes may have changed if the patients had been observed for longer. We advise physicians to review radiographs after elbow dislocation for incarcerated fragments and to examine patients carefully for ulnar neuropathy preoperatively. In cases in which one cannot be certain whether there is an incarcerated fragment after closed reduction of an elbow dislocation, we recommend obtaining a computed tomographic or magnetic resonance imaging study for clarification. If postreduction radiographs were taken through plaster, removal of plaster and re-imaging would likely improve fragment visualization. We recommend exploration of the ulnar nerve only in patients with preoperative nerve palsy. We recommend release of the ulnar nerve if there are ulnar nerve symptoms preoperatively, if the nerve is contused, or if the nerve itself is entrapped in the joint along with the medial epicondyle fracture fragment. This was our practice before the study, and the study results support this practice in that they document a high rate of ulnar nerve palsy for which all possible corrective measures should be undertaken when the ulnar nerve is at risk. Moreover, we recommend identifying and protecting the ulnar nerve in all cases of medial epicondyle fracture open reduction internal fixation in an effort to minimize risk to this critical motor and sensory nerve. Delays in treatment may result in poorer outcomes, specifically with respect to range of motion; hence, we advise exercising extreme caution in ruling out incarceration on presentation to minimize time to operative reduction. Surgeons should advise patients’ families that persistent ulnar neuropathy and heterotopic ossification are common occurrences after this combination of injuries. REFERENCES 1. Carlioz H, Abols Y. Posterior dislocation of the elbow in children. J Pediatr Orthop. 1984;4(1):8e12. 2. Wilkins KE. Fractures and dislocations of the elbow region. In: Rockwood CA, Wilkins KE, King RE, eds. Fractures in Children. 4th ed. Vol. 3. Philadelphia, PA: Lippincott-Raven; 1996:653e887. 3. Rasool MN. Dislocations of the elbow in children. J Bone Joint Surg Br. 2004;86(7):1050e1058. 4. Price CT, Flynn JM. Management of fractures. In: Morrissy RT, Weinstein SL, eds. Lovell & Winter’s Pediatric Orthopaedics. 6th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2006: 1430e1516.
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5. Fowles JV, Slimane N, Kassab MT. Elbow dislocation with avulsion of the medial humeral epicondyle. J Bone Joint Surg Br. 1990;72(1): 102e104. 6. Gottschalk HP, Eisner E, Hosalkar HS. Medial epicondyle fractures in the pediatric population. J Am Acad Orthop Surg. 2012;20(4): 223e232. 7. Beaty JH, Kasser JR. The elbow: physeal fractures, apophyseal injuries of the distal humerus, osteonecrosis of the trochlea, and T-condylar fractures. In: Beaty JH, Kasser JR, eds. Rockwood and Wilkins’ Fractures in Children. 7th ed. Philadelphia, PA: Lippincott, Williams & Wilkins; 2010:566e887. 8. Patrick J. Fracture of the medial epicondyle with displacement into the elbow-joint. J Bone Joint Surg Am. 1946;28:143e147. 9. Roberts NW. Displacement of the internal epicondyle into the elbow joint. Lancet. 1934;224(5785):78e79.
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10. 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(9):1299e1305. 11. Kamath AF, Baldwin K, Horneff J, Hosalkar HS. Operative versus non-operative management of pediatric medial epicondyle fractures: a systematic review. J Child Orthop. 2009;3(5):345e357. 12. Morrey BF, An KN, Chao EYS. Functional evaluation of the elbow. In: Morrey BF, ed. The Elbow and Its Disorders. Philadelphia, PA: WB Saunders; 1993:86e89. 13. Moraleda L, Valencia M, Barco R, González-Moran G. Natural history of unreduced Gartland type-II supracondylar fractures of the humerus in children: a two to thirteen-year follow-up study. J Bone Joint Surg Am. 2013;95(1):28e34. 14. Bowakim J, Marti R, Curto A. Elbow septic arthritis in children: clinical presentation and management. J Pediatr Orthop B. 2010;19(3):281e284.
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