[Extraarticular proximal phalangeal fractures of the hand: Functional conservative management using the Lucerne Cast...

The purpose of our prospective study was to document the clinical and radiological results of conservative-functional treatment of extraarticular proximal phalangeal fractures without immobilisation of the wrist.

The Lucerne Cast (LuCa) resembles a circular metacarpal brace leaving bare both flexion creases, the rascetta and the distal palmar flexion crease. Dorsally, the brace expands to beyond the proximal interphalangeal joints, fixing the metacarpo-phalangeal joints in an intrinsic plus position, thus causing the extensor aponeurosis to tighten and to move distally. Clinical and radiological results of 15 consecutive patients with a total of 20 fractured proximal phalanges were prospectively recorded through a minimum follow-up of 3 months.

Fracture consolidation was achieved in all patients, with nine cases showing a dorsal angulation of 2 °-16°. A slight radial or ulnar deviation, respectively, was present in four cases (3 °-5°). Radiologically, a minor rotational deformity of 5° in supination was found in 3 cases. At a follow-up of 12 weeks, a mean total range of active motion (summation of active range of motion in all three finger joints, TAM) of 240° (minimum 200°, maximum 290°) was achieved.

The results of our prospective clinical trial are comparable to those of already established treatment protocols. Since the Lucerne Cast allows free mobilisation of the wrist joint, the cast is comfortable to wear and may have relevance in the treatment of disabled patients, who only can be mobilised with crutches or walkers.