Fri., 10/17/08 Basic Science, Paper #21, 10:10 am OTA-2008
The Presence and Pattern of Vascular Insufficiency in the Older Patient Suffering an Unstable Ankle Fracture: The Relationship to Skin and Wound Complications
Prof. Keith Willett, FRCS1 (a-AO Research Foundation);
Robert Handley, FRCS2 (a-AO Research Foundation);
Prof. Sallie Lamb, PhD1 (a-AO Research Foundation);
Bridget Gray, RN2 (n); Ashok Handa, FRCS1 (a-AO Research Foundation);
David Coleman, FRCS2 (a-AO Research Foundation);
1University of Oxford, Oxford, United Kingdom;
2John Radcliffe Hospital, Oxford, United Kingdom
Purpose: Variation in the vitality of the skin in elderly ankle fracture patients may account for the higher surgical wound and skin complication rate. This study aims to determine: (1) the cutaneous blood supply (CBS), (2) the effect of ankle fractures on CBS, (3) the relationship of CBS to treatment complications, and (4) the appropriateness of treatment selection—surgical fixation (ORIF) versus casting
Methods: This study is part of a prospective randomized controlled trial comparing two interventions (ORIF and close-contact casting) for isolated unstable ankle fractures in patients over 60 years. Patients with insulin-dependent diabetes mellitus, vascular disease, leg ulceration, and dementia were excluded. Baseline and serial assessments over 6 months were undertaken for skin status, fracture position, union, and complications. Wounds were scored using the ASEPSIS wound viability scale. Vascular assessments were undertaken at 3 days (* only) and 8 weeks postoperatively on both legs: (a) 3-vessel arterial duplex ultrasound, (b) perforator artery patency, (c) Ankle- Brachial Pressure Index (ABPI), and (d)* transcutaneous O2 saturation (TcO2) on lateral and medial ankle skin.
Results: Of 57 eligible patients, 40 agreed to participate (20 ORIF, 20 cast). One died in each group. No patient with an ABPI of <0.70 had complications. Scatter-plot analysis of perforator artery pattern and patency identified no significant differences between the injured and uninjured limbs or complication rate. There was a significantly reduced TcO2 on day 3 in the injured limb compared to the uninjured leg (mean 39 vs 49 mm Hg), an elevated TcO2 at 8 weeks (mean 55 mm Hg) in the injured leg only and a restoration to normal (49 mm Hg) by 6 months. Four participants had a critical TcO2 (<20 mm Hg), two of whom had the only delayed wound-healing or infection complications in the study. Technical measurement problems occurred in 21% of 260 TcO2 readings.
Conclusions: Occult cutaneous vascular insufficiency can be present in this older population with ankle fractures. There is a direct association with wound complications. It is not a result of disruption of the local transfascial perforator end-arteries. ABPI and duplex ultrasound are insensitive. TcO2 is sensitive but impractical as a clinical tool.
Significance: Further clinical research is now required to identify the at-risk patients with poor skin oxygenation and/or to improve nonsurgical treatment for better outcomes in these patients.
If noted, the author indicates something of value received. The codes are identified as a-research or institutional support; b-miscellaneous funding; c-royalties; d-stock options; e-consultant or employee; n-no conflicts disclosed, and *disclosure not available at time of printing.
• The FDA has not cleared this drug and/or medical device for the use described in this presentation (i.e., the drug or medical device is being discussed for an “off label” use). ◆FDA information not available at time of printing. Δ OTA Grant.