Mid-term outcomes following first metatarsophalangeal joint replacement using the Toefit-PlusTM prosthesis

A.G. Titchener, N.S. Duncan, R.A. Rajan

¹Royal Derby Hospital, Derby, United Kingdom 

Introduction: This study evaluates the mid-term results of first metatarsophalangeal joint replacement (MTPJR) for hallux rigidus using the Toefit-Plus^TM prosthesis.

Methods: We prospectively studied the outcomes of 86 MTPJR in 73 patients using the AOFAS-HMI score and radiological follow up over a period from 2006 to 2013, with surgeries performed by a single surgeon at two centres. Patients were reviewed, scored and radiographs obtained pre-operatively and then at intervals of 6 weeks, 6 months, 12 months and then yearly. The mean follow up was 33 months (2-72).

Results: The mean AOFAS score of the patients not requiring revision at 1 year was 92, at 2 years was 94, at 3 years was 91, at 4 years was 99, at 5 years was 93, at 6 years was 100 and at 7 years was 97. 18 joints have either been revised or listed for revision giving a revision rate of 21%; this occurred at a mean of 33 months post-surgery. Reasons for revision included loosening of components in 13, infection in 1, dislocation in 2, malalignment in 1 and persistent pain in 1. Eight patients sustained intra-operative fractures requiring circlage wiring, of which 7 went on to union and one required revision. 25 patients had evidence of radiological loosening of which 22 were around the phalangeal component and 3 were around the metatarsal component.

Conclusions: First MTPJ replacement resulted in improved outcomes in patients with hallux rigidus who do not require revision in the medium term, however the revision rate is unacceptably high and as such we have discontinued use of this prosthesis. Radiological loosening of the components is high and needs monitoring for progression which may necessitate revision.

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