LATERAL CONDYLE FRACTURE THROUGH THE CAPITELLUM IN A CHILD

THOM BROWN, M.D., Resident, Orthopaedic Surgery

WILLIAM MACKENZIE, M.D., Attending, Pediatric Orthopaedic Surgery

November 15, 1995

CLINICAL CASE PRESENTATION

ORTHOPAEDIC DEPARTMENT

THE ALFRED I. DUPONT INSTITUTE

WILMINGTON, DELAWARE

CASE HISTORY:

• HISTORY: Five and 5/12 year old white male sustained a fall onto his outstretched right arm with immediate complaints of pain and swelling in his right elbow with an inability to move the arm secondary to pain.
• PHYSICAL EXAM: Physical examination revealed swelling, tenderness and crepitus over the lateral aspect of the elbow. The skin was intact and neurovascular examination of the right upper extremity was without deficits.
• XRAYS: Radiographic examination of the right upper extremity revealed a displaced fracture involving the lateral condylar physis exiting through the substance of the capitellum.
• TREATMENT: The patient was taken to the operating room where under general anesthesia and tourniquet control the fracture was exposed utilizing an anterolateral approach, taking care not to disturb the posterior vascular pedicle of the lateral condyle. Following adequate reduction of the fracture, 2 diverging k-wires were placed across the fracture site. The patient was immobilized in a long arm cast at 90 degrees until radiographic evidence of healing was apparent. The long arm cast and k-wires were removed in clinic.

ETIOLOGY

17% of all pediatric elbow fractures.

More common in summer months 5-10 years of age (2-14)

Mechanism: varus stress to an extended elbow with supinated forearm

CLASSIFICATION

ANATOMIC: (Milch)

• Milch I- Fracture extends through the ossification center and exits at the radiocapitellar groove. The lateral crista is intact, decreasing the likelihood of elbow dislocation. (Salter-Harris IV)

• Milch II- Fracture line follows the physis completely medially, exitin- through the trochlear notch rendering the humero-ulnar joint unstable. (Salter-Harris II)

DISPLACEMENT: (Rutherford)

• Stage I- minimal displacement with intact articular surface
• Stage II- rotation of the fragment with disruption of the articular surface
• Stage III- fragment is rotated and displaced

DISPLACEMENT RISK: (Finnbogason)

• Fracture line can not be followed to the epiphyseal cartilage (0/65 displaced)
• Fracture line clearly exits through epiphyseal cartilage (6/35 displaced)
• Fracture gap equal medially and laterally (5/12 displaced)

TREATMENT

• Nondisplaced (stage I): posterior splint vs. long arm cast at 90 degrees flexion with supinated forearm. CLOSE FOLLOW-UP IMPORTANT because of high incidence of late displacement and eventual non\malunion.

• Displaced (stage II/III): closed reduction and percutaneous pinning if reducible closed. If not, ORIF with percutaneous pinning, recommended. Post-operative Management: Long ann cast at 90 degrees until radiographic signs of healing are evident.

COMPLICATIONS

• Cubitus Varus: Secondary to matunion or capitellar overgrowth. No rotation as in supracondylar fractures. The deformity is in the coronal plane only, and usually does not require treatment.

• Fishtail Deformity: Secondary to a break between the ossific nucleii of the capitellum and trochlea resulting in disruption of the lateral trochlear epiphyseal vessel, resulting in a deficient lateral lip of the trochlea. This is also treated conservatively.

• Cubitus Valgus: Secondary to non-union and proximal migration of the fragment with subsequent elbow instability and eventual tardy ulnar nerve palsy (20+ years). Cubitus valgus secondary to physeal closure has rarely been reported. Treatment- transposition +\- osteotomy with ORIF, only if symptomatic or unstable.

• Late Appearing Fractures: Undiagnosed/untreated fractures >6 weeks post-injury. Some studies suggest a conservative approach because of the high risk of capitellar AVN and stiffness secondary to the wide surgical exposure. Flynn has reported good results utilizing a limited exposure with pin and bone pe- fixation for slightly displaced fractures.

CONCLUSIONS

1. Fractures of the lateral condylar physis that exit through the capitellum should be treated with the same indications as a Milch II fracture with emphasis placed on achieving and maintaining articular congruity until healed by closed or more often open means.

1. The length of time to maintain internal fixation and casting should be dictated by the radiographic appearance of the healing fracture more so than the length of time of immobilization. Displacement with has been reported between 3 and 4 weeks post fracture.

REFERENCES

1. Dhillon, K.S., et al., Delayed Management of the Lateral Condyle in Children. Acta Orth. Scand. 1988; 59(4), 419-424.

1. Finnbogason, T., et al., Nondisplaced and Minimally Displaced Fractures of the Lateral Humeral Condyle in Children: A Prospective Radiographic Investigation of Fracture Stability. JPO,1995; 15, 422-425.

1. Flynn, J., Nonunion of Slightly Displaced Fracture of the Lateral Humeral Condyle in Children: An Update. JPO, 1989; 9,691-696.

1. Flynn, J, and Richards J., Nonunion of Minimally Displaced Fractures of the Lateral Condyle of the Humerus in Children. JBJS, 1971, 53A No. 6, 1096-1 101.

1. Jakob, R. et al., Observations Concerning Fractures of the Lateral Humeral Condyle in Children. JBJS 57B No. 4,430-436.

1. Masada, K, et al., Osteosynthesis for Old Established Non-Union of the Lateral Condyle of the Humerus. JBJS, 1990, 72A, -)2-40.

1. Marzo, J., et al., Usefulness and Accuracy of Arthrocraphy in Manacement of Lateral Humeral Condyle Fractures in Children. JPO, 1990, 10, 317-32 1.

1. Milch, H., Fractures and Fracture-Dislocations of the Humeral Condyles. J. Trauma, 1964, 4, 592-607

1. .Roye, D., et al., Late Sur-ical Treatment of Lateral Condylar Fractures in Children. JPO, 1991, 11, 195-199.

1. Rutherford, A., Fractures of the Lateral Humeral Condyle in Children. JBJS, 1985, 67A No. 6, 851-856.

1. Wilkins, K., Operative Management of Upper Extremity Fractures in Children. American Academy of Orthopaedic Surgeons Monograph Series. 1994, 66-70