Anatomical reconstruction of first ray instability hallux valgus with a medial anatomical TMTJ1 plate

First tarsometatarsal joint (TMTJ1) arthrodesis is a powerful tool for hallux valgus correction. Past criticism of the TMTJ1 arthrodesis has focused on high non-union rates, and consequent need for delayed weightbearing as prevention. In this study we present a selection and treatment protocol to minimise non-union while allowing early weightbearing.

All TMTJ1 arthrodesis procedures for hallux valgus performed by the senior surgeon over the period June, 2016 to July, 2019 were included. An anatomically-designed, medial TMTJ1 plate and screw compression was utilised for TMTJ1 arthrodesis. The construct was augmented with synthetic intermetatarsal stabilisation. All patients were kept non-weightbearing for 2 weeks, followed by progressive weightbearing as tolerated for 4 weeks. Minimum follow-up was 1 year.

300 modified Lapidus procedures were performed for hallux valgus with mean IMA 17° (Range: 14-29). Mean age was 58 years, with 93% female. 284 (94%) had an Akin osteotomy, while 222 cases (74%) were associated with another forefoot procedure. Patients began progressive weight bearing as tolerated from 2 weeks. All were fully weight bearing by 8 weeks post-operatively. There was a 100% union rate in this group. Mean AOFAS Hallux MTP-IP scores rose from 59 pre-operatively to 97 post-operatively. One plate was removed due to tibialis anterior impingement. There were no recurrences at final follow-up.

We describe a selection and treatment protocol for TMTJ1 arthrodesis for hallux valgus. This yields high union rates while allowing early weight bearing.

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