Objective: To determine the relationship between the aetiological factors, duration of ankylosis and the types of ankylosis and to evaluate the outcome of different treatment modalities used.
Design: Retrospective study of cases managed.
Setting: University teaching hospital at Ibadan, Nigeria.
Subjects: Thirty six cases treated between 1982 and 1997.
Results: Infection related aetiological factors were 66.6% while trauma was 27.8%. The relationship between aetiological factors and type of ankylosis classified by anatomic site, was statistically significant. Results suggest that infection-related aetiological factors are likely to give rise to extracapsular ankylosis, while trauma results in intracapsular ankylosis. Twenty five per cent reported for treatment within 12 months of onset of ankylosis while 72.2% reported after 24 months. The relationship between ankylosis of 24 months duration and above, and classification of ankylosis according to tissue type was also significant (p < 0.05) and suggests that ankylosis of such duration is likely to be bony or mixed fibrous and bony. Of the types of ankylosis, 77.8% had bony components while 22.2% were of the fibrous variety. As regards treatment, interpositional arthroplasty with the masseter muscle produced results that were more consistent and satisfactory than gap arthroplasty.
Conclusion: The aetiological factors and duration of ankylosis influenced the type of ankylosis.