[Anatomy of the trapeziometacarpal joint in the context of arthroplasty]

[Resection arthoplasty of the trapezium with ligament reconstruction and tendon interposition and variations]

OBJECTIVE

Creation of a pain-free, flexible and stable (pseudo) joint between the carpus and the base of the 1st metacarpal bone.

INDICATIONS

Painful carpometacarpal (CMC)‑I joint due to primary or secondary osteoarthritis, CMC‑I instability.

CONTRAINDICATIONS

Carpal instability, local infection, tumors.

SURGICAL TECHNIQUE

Resection of the trapezium (and of the arthritic joint surfaces in CMC‑I and STT [scaphoid-trapezium-trapezoid-joint]), stabilization of the base of the 1st metacarpal bone by suspension with a distally pedicled strip of the flexor carpi radialis tendon or variants thereof.

POSTOPERATIVE MANAGEMENT

Immobilization in a splint for 3-5 weeks, followed by hand therapy.

RESULTS

Worldwide for almost 40 years, regardless of the exact technique, almost always (90%) significant pain reduction, increased strength in the grip and slightly less in the pinch grip, very good mobility, 85-95% very satisfied patients and very good long-term results.

The influence of K-wire transfixation on proximalization of the first metacarpal after resection suspension interposition arthroplasty

INTRODUCTION

Osteoarthritis of the first carpometacarpal joint is a common degenerative disease and surgical treatment includes resection suspension interposition arthroplasty (RSIA) with or without temporary transfixation of the first metacarpal. One major drawback includes proximalization of the first metacarpal during the postoperative course. Specific data comparing different transfixation techniques in this context is sparse.

MATERIALS AND METHODS

In this retrospective study, we measured the trapezial space ratio (TSR) in 53 hands before and after RSIA to determine the proximalization of the first metacarpal depending on the type of Kirschner (K)-wire transfixation. We, therefore, compared transfixation of the first metacarpal to the scaphoid with one K-wire (1K) to transfixation of the first metacarpal with two K-wires (2K), either to the carpus (2Ka), or to the second metacarpal (2Kb), or to both second metacarpal and carpus (2Kc).

RESULTS

While preoperative TSR did not differ between group 1K and 2K (p = 0.507), postoperative TSR was significantly higher in group 2K compared to 1K (p = 0.003). Comparing subgroups, postoperative TSR was significantly higher in group 2Kc than 1K (p = 0.046), while we found no significant difference comparing either group 2Ka or 2Kb to 1K (p = 0.098; p = 0.159). Neither did we find a significant difference within 2K subgroups, comparing group 2Ka and 2Kb (p = 0.834), 2Ka and 2Kc (p = 0.615), or 2Kb and 2Kc (p = 0.555).

CONCLUSIONS

The results of our study suggest that transfixation with two K-wires should be preferred to transfixation with one K-wire after RSIA. Specifically, transfixation from first to second metacarpal and from first metacarpal to carpus resulted in least proximalization of the first metacarpal postoperatively.

Outcomes after thumb carpometacarpal joint stabilization with an abductor pollicis longus tendon strip for the treatment of chronic instability

INTRODUCTION

Instabilities of the thumb carpometacarpal (CMC) joint, caused by idiopathic ligamentous hyperlaxity, trauma or other conditions may lead to pain, functional impairment and eventually osteoarthritis. Several techniques have been described to enhance stability of the CMC 1. The aim of this study was to evaluate postoperative outcomes after CMC 1 joint stabilization using a soft-tissue procedure in patients with chronic instability.

MATERIALS AND METHODS

This study was designed as a retrospective study with a single follow-up visit after a minimum of 1 year postoperatively. All patients who underwent stabilization of the CMC 1 with an abductor pollicis longus (APL) tendon strip for chronic, habitual instability were re-assessed using clinical examination, dedicated outcome scores [Visual Analogue Scale (VAS); The Disability of the Arm, Shoulder and Hand (DASH) score; Nelson score; Kapandji opposition score], grip and pinch strength measurements, and radiographic examination.

RESULTS

12 patients (15 operated thumbs) with a mean age at surgery of 23.2 (± 9.3) years were included after a mean follow-up period of 3.5 (± 1.3) years. The postoperative outcomes indicated excellent results, with a mean DASH score of 13.3 (± 11.3), VAS 1.1 at rest (and 2.8 during stress) and Nelson score of 87.7 (± 11.3). Postoperative grip, pinch strength and passive stability were not significantly different between operated and non-operated sides (p = 0.852; p = 0.923 and p = 0.428, respectively). We observed one case of recurrent instability besides no other complications. However, patients with trapezium hypoplasia (5 of 12) were more prone to signs of radiographic instability during stress testing.

CONCLUSIONS

Thumb carpometacarpal stabilization with an APL tendon strip yielded excellent clinical outcomes and low morbidity in the mid-term. However, long-term follow-up is needed to assess specifically whether patients with trapezium hypoplasia may be more prone to clinical symptom recurrence than those with normal anatomy.

LEVEL OF EVIDENCE

Level IV.