Bilateral type 1 capitellar fractures: a case report

Abstract

There have been no cases of bilateral type I capitellar fractures reported in the UK, and only two reported world-wide. This report describes the clinical case of a 26-year-old woman, who fell sustaining this injury, and how careful management resulted in an excellent outcome. This case highlights the rarity of this injury, its potential morbidity, and an approach to its management which produces excellent clinical results.

Capitellum fractures are rare injuries of the elbow, usually presenting in young adults. The mechanism of injury follows a fall on the outstretched upper limb causing axial compression of the radial head against the capitellum. This produces a shearing type force, resulting in a variable sized bone fragment. The exact fracture configuration is dependent on the degree of flexion of the elbow and position of rotation at the time of injury. The type 1 (Hahn–Steinthal fracture) consists of a large fragment of cancellous bone of the articular surface of capitellum and may include a portion of the trochlea, typically the lateral third. There are several potential treatment options including fragment excision, manipulation and K-wire fixation, and open reduction and internal fixation with cancellous or headless screws. There have been no cases of bilateral type I capitellar fractures reported in the UK, and only two reported world-wide.^1,2

Case history

A 26-year-old white woman lawyer sustained a fall landing on both outstretched hands while running recreationally. She was 5 feet 6 inches in height with no significant past medical history. She was a non-smoker, had a low alcohol intake, and took no regular medication. She underwent routine imaging including plain radiographs, and computed tomography (CT) scanning. She was treated surgically 3 days following the injuries, with open reduction and internal fixation of both elbows. Curved lateral Kocher approaches were used. The articular fragments were stabilised with two subarticular ‘Acutrax’ headless screws on the left (Fig. 1), and one ‘Acutrax’ and two 4-mm cannulated, partially threaded screws on the right (Fig. 2).

Figure 1.

Left elbow fracture and fixation.

Figure 2.

Right elbow fracture and fixation.

Initially, she was protected with full casts for 2 weeks postoperatively. She managed well with support at home, despite her bilateral injuries, but required help with toileting, washing and dressing. At 2 weeks, she demonstrated range of movement 60–90º. At this stage, she was put into hinged braces locked at 50–100º and started intensive physiotherapy; this allowed her to regain her independence rapidly. At 4 weeks, the range of movement was increased to 45–120º. At 8 weeks she, demonstrated a 15º extension lag on the right and 30º on the left and the braces were removed. At 3 months after the injuries, she lacked only 10º extension bilaterally, with full supination and pronation. Radiographs demonstrated union with no evidence of avascular necrosis. At 3 years, there was restoration of range of movement (Fig. 3) and no loss of function.

Figure 3.

Postoperative range of movement.

Discussion

The goal of operative treatment is anatomical reduction and fixation to minimise the risk of non-union. Fracture healing in the absence of periosteum such as here would be endosteal. The bone fragments have potentially lost their blood supply, and the surrounding intra-articular synovial fluid has angiogenic–inhibiting factors, both of which can inhibit fracture healing. Therefore, urgent gentle anatomical reduction is necessary, which may permit re-establishment of some vascular continuity and prevent synovial non-union.

Two surgical approaches for open reduction and internal fixation are described including the lateral modified Kocher approach, and the posterior approach via an olecranon osteotomy. The posterior approach to the capitellum offers no biomechanical advantage to fixation, and the authors have found that, in the absence of other intra-articular injury, the potential complication rate associated with an osteotomy unacceptable. An arthroscopic approach has also been described with good results.³

Method of fixation is dependent on the experience of the operating surgeon, and the fracture configuration. The use of standard compression and headless screws is well documented. The use of a biodegradable screw has also been described.⁴

Previous authors have immobilised capitellum fractures for 3 weeks with a poorer outcome.^5,6 Our results suggest not only is adequate surgical stabilisation necessary for a successful result, but also earlier active mobilisation, with a controlled increase to range of movement and return to independent living.