Stabilising total ossicular replacement prosthesis for ossiculoplasty with an absent malleus in canal wall down tympanomastoidectomy - a randomised controlled study.

OBJECTIVES: To compare two titanium total ossicular replacement prosthesis (TORP) stabilisation techniques in canal wall down mastoidectomy presenting with footplate only and absent malleus handle.

DESIGN: Prospective, controlled, randomised study.

SETTING: Tertiary Otology Department.

PARTICIPANTS: Patients operated on with canal wall down mastoidectomy between 1999 and 2009 were randomised into two groups. Two techniques enhancing the TORP stability were compared: Hüttenbrink's method (63 patients, Group 1) and author's (GB) procedure (62 patients, Group 2). Hüttenbrink's technique consists in placing a cartilage shave with a hole in the middle over the footplate. Through this hole, the end of the TORP is accommodated. The author's method involves using a cartilage split in the middle, to lodge the TORP's shaft at one end and to lay the opposite end over the fallopian canal.

MAIN OUTCOME MEASURES: Mean postoperative air-bone gap, hearing gain and air-bone gap closure within 20 dB. Auditory outcomes were evaluated at 1 year postoperatively.

RESULTS: Postoperative air-bone gap closure within 20 dB (successful outcome) at 1 year was achieved in 59% of patients in Group 1 and 72% in Group 2 (P = 0.03). Mean postoperative air-bone gap was 24.4 ± 10.8 dB for Group 1 and 20.17 ± 9.8 dB for Group 2. The difference is 4.23 dB (95% confidence interval, 0.65-07.81), statistically significant: P = 0.02. Hearing gain was 20.3 ± 9.5 in Group 1 and 25.1 ± 10.2 in Group 2, significantly superior: P = 0.007.

CONCLUSION: Better hearing outcomes for author's method could be demonstrated, but our sample size cannot exclude small and possible trivial, group differences.