First metatarsophalangeal joint arthrodesis vs implant arthroplasty;
Prospective randomised clinical trial.

The great toe is vital for normal, pain free ambulation. Osteoarthritis of the
first metatarsal phalangeal joint (MTP I), also called hallux rigidus, leads to
a painful great toe. Patients experience pain during ambulation, especially
during the push-off phase of gait. When surgery is indicated, four techniques
are widely used for hallux rigidus; cheilectomy, resection arthroplasty,
arthrodesis and implant surgery.
Arthrodesis has been the hallmark for treatment of osteoarthrosis of the MTPI
joint for active patients between 18 and 60 years of age because it maintains
column stability of the first ray. Potential problems of arthrodesis include
malunion, non-union and degeneration of the IP joint, although the clinical
importance of IP arthritic changes has been debated. Many different techniques,
with variable success, for achieving union of the MTPI arthrodesis have been
described.
Endoprostetic implants are relatively new. Silicone implants like the
arthroplasty developed by Swanson resulted in foreign body reactions and
periarticulair bone loss. Subsequent implants, in particular the metallic
hemiarthoplasty with or without polyethylene articulations, have been more
successful. Still, implants are prone to wear of the material and show higher
rates of infection compared to other techniques.
Arthrodesis of the MTPI-joint has shown its worth in the treatment of hallux
rigidus. If positional requirements are met and fusion is achieved, this
technique relieves patients of pain in the great toe. An even better
biomechanical approach would be substituting the affected joint with a stable
and long living implant. Thus far the longevity of a MTPI implant has been
doubtful and its use controversial.

The main objective of this study is to show the differences in outcome of two
fundamentally different operational techniques in hallux rigidus. It will
assess pain, range of motion and activity level in both groups using the
standardised AOFAS-HMI score as well as a VAS pain score. This score has a
maximum of 100 points for a patient feeling no pain, having a full range of
motion and full stability of both the MTPI joint and the IP joint while
experiencing no limitations in activities.
Secondary objectives are biomechanical assessments of the two groups of
patients, both before and after operation, by measurement of foot pressure
during gait and a 24 hours gait analysis. Furthermore complications,
(sports)activities, quality of life and satisfaction with the treatment will be
recorded. Radiological angles of the hallux position, union of the arthrodesis
and osteolytic appearance of the bone will be recorded.

Prospective randomised multi-centre comparative clinical trial with intention
to treat principle.

1. Arthrodesis of the MTPI joint.

or

2. Implantation of a MTPI prosthesis.

The burden for patients consist mainly of the fact that they will not know wich
operation will be performed untill the operation itself. They were already
considered for operative treatment so no extra burden lies within the operation
itself. Patients follow-up will take up some more of their time for answering
the questionnaires and participation in the movementmeasurements

Risks for the patients are the same if they did not cooperate in this study
since they would have been treated with one of the operational techniques.