Does Arthrodesis of the First Metatarsophalangeal Joint Correct the Intermetatarsal M1M2 Angle? Analysis of a Continuous Series of 208 Arthrodesis Fixed with Plates

SLR - December 2015 - Shanique Bingham

Reference: Dalat F, Cottalorda F, Fessy MH, Besse JL. Does Arthrodesis of the First Metatarsophalangeal Joint Correct the Intermetatarsal M1M2 Angle? Analysis of a Continuous Series of 208 Arthrodesis Fixed With Plates. Orthop Traumatol Surg Res. 2015 Oct; 101(6): 709-714.

Scientific Literature Review

Reviewed By: Shanique Bingham, DPM
Residency Program: Bridgeport Hospital Yale New Haven

Podiatric Relevance: This article is relevant to the podiatric surgeon, as 1st MTPJ arthrodesis is a common procedure that is often done in the treatment of painful 1st ray deformities, recurring deformity after surgical correction and severe hallux-abducto valgus deformities. There is no definite consensus in the literature on what pre-operative angles work for long term correction. It is stated that there is a wide range of angles that are considered normal and indications for certain procedures change. This study is enlightening as it provides an abstract that the podiatric surgeon can use when making pre-operative decisions, not just first ray angles but the position of the fusion, time to union and post op complications, with just the isolated 1st MTP plate arthrodesis.

Methods: This was a prospective study from June 2007 and March 2011 on 208 patients treated with 1st MTP plate arthrodesis. Pre-operatively the patients were evaluated clinically and radiographically. The post-operative follow-up periods were 45 days, three months and one year. The mean age was 62.4 (+ or – 9.9 years) with 89 percent women and 20 percent of the patients with previous forefoot surgery (excluding fusion). Etiologies include severe hallux valgus M1P1 angle greater than 40%, hallux rigidus, surgical revision and rheumatoid foot. All the procedures were performed by the same surgeon. Surgical technique include a medial approach with lateral release, after joint preparation the arthrodesis was osteosynthesized with an anatomical plate, prebent at 5◦ including a phalangeal arm for an oblique metatarsophalangeal screw in compression, complementary to the four 2.7-mm dorsal screws. The screws were not locked in the plate. Proper positioning of the MTP-1 arthrodesis was checked intraoperatively using fluoroscopy.

Results: The specific results of this study are as follows: Out of 208 patients, the overall correction of pre-operative level of abnormal angles (33.9 plus or minus 18.0 degrees have been corrected to 13.3 degrees plus or minus 19.7 degrees). It did not matter the level of severity as there was the same significant difference for pre- and post-operative M1P1 and M1M2 angles. Also, the greater the metatarsus varus, the higher the post-operative M1M2 was; however it remained less than 10 degrees. There was no significant difference for the postoperative M1M2 angle between the different etiologies except between the hallux values and hallux rigid groups. There were only two patients out of 208 that had a post-operative angle greater than 10 degrees (They both had first-ray cuneometatarsal arthritis). The specific results were that the similarity of the surgical procedure performed on various pre-operative etiologies and deformities had the same corrective outcome.

Conclusion: The authors concluded MTP1 arthrodesis is an intervention that simultaneously corrects the M1M2 and M1P1 angles, including substantial deformities. The above results demonstrate the effectiveness of the correction on increased deformities. The higher deformity angle the greater correction obtained from MTP1 arthrodesis. The information of this study will help determine surgical procedures for various etiologies. Also the greater the pre-operative metatarsus varus, the greater the gain obtained. Finally cuneometatarsal arthrodesis associated with MTP-1 arthrodesis can help correct the angles related with osteoarthritis of the cuneometatarsal joint that is associated with major increase in angle of the M1M2. The results of the paper demonstrate the effectiveness of the surgical procedure with severe etiologies and should be researched more aggressively.