ARTHROSCOPIC ANKLE ARTHRODESIS USING A HEADLESS SCREW FIXATION SYSTEM

Abstract

Introduction: Arthroscopic ankle arthrodesis has been shown in other studies to be a viable alternative to open arthrodesis for end stage arthritis. Its demonstrated advantages include comparable or better rates of fusion, reduced morbidity, shorter hospital stays, quicker times to union and reduced wound complications, especially in patients prone to wound healing problems. However, two main restrictions have been shown in the literature; its limited ability for deformity correction and the subsequent need for metalwork removal, commonly for pain or prominence.

Aims: This study sought to investigate the need for metalwork removal, with the specific question of whether the use of a headless screw fixation system reduces the need for subsequent metalwork removal for pain or prominence.

Materials and Methods: Between 2000 and 2007, 37 arthroscopic arthrodesis using the AcutrakTM headless screw fixation system were carried out by the senior author (AK). We reviewed the case notes of all these patients to determine tourniquet times, length of stay in hospital, time to clinical and radiological union, complication rates and the requirement for metalwork removal for pain or prominence.

Results: Of the 37 patients, 22 (59.5%) were male and 15 (40.5%) were female. The average age at surgery was 67 yrs (range 37–86 yrs), average duration of follow up was 37 months (range 6–94 months). The average tourniquet time was 84 minutes (60–120 minutes). The median length of stay was 2 days (1–5 days)

The average time to clinical union was 14 weeks (6–23 weeks) and the average time to radiological union was 16 weeks (6–37 weeks).

There were 6 (16%) non-unions in this series 2 of which were fibrous non-unions. Both patients with fibrous non-unions experienced minimal or no symptoms and did not require further intervention. Of the 4 other non-unions, 3 were revised using an open technique, the fourth patient again being minimally symptomatic and not wanting further surgery.

1 patient suffered a traumatic displacement of the arthrodesis, requiring an open revision which went on to successful union at 3 months.

There were no other complications in this series and, of note, there were no cases of metalwork removal for prominence or pain.

Conclusion: Headless screw fixation systems have the theoretical advantage of allowing the entire length of the screw to be buried in bone, thus eliminating the problem of metalwork prominence. This should therefore obviate the need for further surgery to remove the prominent screws. Our study corroborates this, with none of our patients requiring metalwork removal for prominence.