The first carpometacarpal (CMC) joint, located at the base of the thumb and formed by the junction between the first metacarpal and trapezium, is a common site for osteoarthritis of the hand. The shape of both the first metacarpal and trapezium contributes to the intrinsic bony stability of the joint, and variability in the morphology of both these bones can affect the joint's function. The objectives of this study were to quantify the morphological variation in the complete metacarpal and trapezium and determine any correlation between anatomical features of these two components of the first CMC joint. A multi-object statistical shape modelling pipeline, consisting of scaling, hierarchical rigid registration, non-rigid registration and projection pursuit principal component analysis, was implemented. Four anatomical measures were quantified from the shape model, namely the first metacarpal articular tilt and torsion angles and the trapezium length and width. Variations in the first metacarpal articular tilt angle (- 6.3° trapezium width (10.28 mm trapezium length (12.25 mm trapezium width may be important anatomical features which could be used to advance early detection and treatment of first CMC joint osteoarthritis.
We reviewed the incidence and treatment of flexor carpi radialis tendinitis in 77 patients (81 thumbs) who had trapeziectomy and abductor pollicis longus suspensionplasty for thumb carpometacarpal joint arthritis. Eighteen patients, 20 wrists (25%) had flexor carpi radialis tendinitis. The onset was 2-10 months (mean 4.7) after surgery. Two cases had preceding trauma. Eight cases (40%) responded to splinting and steroid injection. Ten patients, 12 wrists (60%) underwent surgery after failing non-operative treatment. Eleven wrists had frayed or partially torn flexor carpi radialis tendon and one had a complete tendon rupture with pseudotendon formation. Flexor carpi radialis tenotomy and pseudotendon excision were performed. All operated patients obtained good pain relief initially post-operatively. However, the pain recurred in two patients after 8 months. One required a local steroid injection for localized tenderness at the site of the proximal tendon stump. The other patient required a revision operation for scaphotrapezoid impingement. Both obtained complete pain relief. Our study has shown a high incidence of flexor carpi radialis tendinitis following trapeziectomy and abductor pollicis longus suspensionplasty. Patients should be warned about this potential complication.
Study a collaboration between Malaysia and Australia