Abstract
Introduction: Arthrodesis of 1st MTPJ is performed using various fixation techniques including lag screws, dorsal plate and screws, K-wiring. We evaluated the strength of fixation using two staples placed at right angles.
Methods: Ten pairs of cadaveric feet were dissected to harvest the hallux MTPJ. Planar cut of articular surfaces using a micro-saggital saw. The bony ends were then approximated with an intervening blade and fixed using 2 staples placed at right angles. The specimen was supported on either ends and subjected to 3 point loading using a materials testing machine (Instron). The load at which the joint opened up sufficiently to let the blade fall was recorded. The load at which the construct failed was then recorded
Results: The joint opened up at an average of 41 Newtons. The load to failure was 130 Newtons. The corresponding average values in kilograms were 4.19 kilograms for the opening of the joint and 12.61 kilograms for the failure of the construct. On full weight bearing using the heel weight bearing shoes that we normally use post-operatively, the forces going through the forefoot were 0 newtons/kilograms, calculated using a TEK SCAN (measures the foot pressure on walking)
Conclusion: It is safe to walk patients using a heel weight bearing shoe (Benefoot post op wedge shoe) following 1st MTPJ fusion using staples (uniclip-NewDeal). This is a major advantage compared to other methods of fixation that require plaster cast immobilisation thus reducing inconvenience, plaster expenses and possible complications like DVT.
Correspondence should be addressed to: D. Singh, BOFAS, c/o BOA, The Royal College of Surgeons, 35–43 Lincoln’s Inn Fields, London WC2A 3PE.
