Thumb carpometacarpal osteoarthritis is, next to osteoarthritis of the distal interphalangeal joints, the second most common degenerative disease of the hand [1, 2]. It affects 10 to 15 times more women than men, especially from the age of 50 [3, 4, 5]. In 20-30% of cases, both hands are affected [3].
In the development of idiopathic thumb carpometacarpal osteoarthritis, rotational forces with eccentric loading of marginal areas and consequently locally high pressure peaks may play a role during opposition movement in the thumb carpometacarpal joint (TCMJ) [4, 6]. Other possible influencing factors include a mismatch of the joint surfaces between the trapezium bone and the base of the first metacarpal or a shape change of the trapezium bone with steep positioning of the joint surface [3, 4]. The most significant cause of thumb carpometacarpal osteoarthritis is considered to be ligament instabilities, which are traumatically induced or arise from long-term overuse of the joint or are a consequence of general ligament laxity. Ligament instabilities of the TCMJ lead to dorsoradial translation of the MC-I base during forceful pinch grip with punctual overuse of the joint surfaces [7]. Secondary thumb carpometacarpal osteoarthritis as a result of trauma (e.g., MC-I base fracture) or rheumatic or septic arthritis is rarer [3, 4].
For diagnostic confirmation, classification of the disease stage, and treatment planning, conventional X-ray images of the thumb in 2 planes are required. The radiological findings allow the staging according to Eaton and Littler [8].
Radiological Classification of Thumb Carpometacarpal Osteoarthritis according to Eaton and Littler
Stage I | Normal, possibly widened joint space (effusion), slight subluxation of the first metacarpal bone |
Stage II | Slight joint space narrowing, osteophytes smaller than 2 mm, pronounced subluxation of the first metacarpal bone |
Stage III | Pronounced joint space narrowing up to elimination of the joint space, osteophytes larger than 2 mm |
Stage IV | Joint destruction, cystic, sclerotic remodeling processes, pronounced subluxation of the first metacarpal, STT osteoarthritis |
(STT joint = scaphotrapeziotrapezoid joint)
Since the radiological severity of thumb carpometacarpal osteoarthritis does not necessarily correlate with the clinical symptom picture, but the subjective degree of pain intensity is also decisive for treatment planning, the clinical symptom picture should be captured with the staging according to Alnot and Saint Laurent [9].
Staging of Thumb Carpometacarpal Osteoarthritis according to the clinical pain symptomatology according to Alnot and Saint Laurent
Stage 0 | No complaints |
Stage I | Pain during certain activities |
Stage II | Pain during everyday activities |
Stage III | in addition to stage II episodes of rest pain |
Stage IV | (almost) constant pain |
The goal of conservative treatment of thumb carpometacarpal osteoarthritis is pain relief, among other things through inhibition of the local inflammatory reaction:
- Temporary intake of NSAIDs
- Intra-articular injections of corticosteroids, hyaluronic acid [10, 12-14]
- Radiosynoviorthesis [15]
- Orthosis for a maximum of 2 weeks [16]
The surgical therapy of thumb carpometacarpal osteoarthritis is performed stage-appropriately according to the classification by Eaton and Littler. A distinction is made between joint-preserving and joint-resecting procedures.
Joint-preserving procedures:
- Ligamentoplasties
- Arthroscopy
- Denervation
- Extension osteotomy
Joint-resecting procedures, elimination of opposition movement in the TCMJ:
- Endoprosthetic replacement of the TCMJ
- Arthrodesis of the TCMJ
- Resection arthroplasty
Resection Arthroplasty
Due to its high success and low complication rate, resection arthroplasty (RA) is considered the gold standard of surgical treatment for advanced thumb carpometacarpal osteoarthritis in stages III and IV according to Eaton and Littler [3, 4, 17]. The surgical principle of RA is based on the removal of the arthritic joint by resection of the trapezium bone. For the subsequent stabilization of the thumb ray, there are a variety of technical variants.
The first trapeziectomy was described in 1949 by Gervis, who performed a reefing capsular suture proximal to the MC-I base for stabilization of the thumb ray [18]. The formation of stable scar tissue was intended to prevent painful proximalization of the thumb ray.
To support the thumb ray, interposition plasties were later developed, in which autologous material is introduced into the trapezium cavity, such as a rolled-up, distally pedicled FCR tendon strip or a tendon ball formed from a free palmaris longus tendon transplant [19].
Stabilization of the thumb ray in suspension arthroplasties is achieved through direct or indirect reconstruction of the intermetacarpal ligaments between the MC-I and MC-II bases. For this, tendon strips from the FCR, APL, or ECRL tendons are used in variable techniques.
In the resection-suspension arthroplasty according to Epping, after complete trapeziectomy, a distally pedicled strip from the FCR plasty is prepared, passed through a drill hole in the MC-I base, and blocked in the drill hole with a bone wedge from the resected trapezium bone according to the original technique described in 1983 [20].
The suspension can be extended by an additional interposition plasty of the overlong prepared FCR tendon (technique according to Burton and Pellegrini or Ligament-Reconstruction-Tendon-Interposition [LRTI] arthroplasty). Here, the remaining tendon strip is sewn together into a ball and fixed with sutures for interposition in the former trapezium cavity [21]. The resection-suspension-interposition arthroplasty is the most commonly used technique for surgical treatment of thumb carpometacarpal osteoarthritis in the USA and Europe [22, 23].
In follow-up examinations, long-term and independent of the suspension and interposition technique, a high patient satisfaction of around 90% was shown with very good, mostly free mobility of the thumb as well as normalization of gross strength and improvement of pinch and key grip strength. In 80% of cases, patients were symptom-free, in 90% at least significantly symptom-reduced. Furthermore, a low complication rate of about 1-5% was shown [4, 24-27]. After RA, however, a long rehabilitation phase must be expected, sometimes up to 6 months [4, 24].
In a prospective randomized study, 1 year after the operation, no difference in subjective and functional outcome was shown between patients who received a pure trapeziectomy, patients with trapezium resection and palmaris longus tendon interposition, and patients with trapeziectomy and subsequent suspension and interposition arthroplasty (Ligament-Reconstruction-Tendon-Interposition [LRTI] arthroplasty). However, patients with tendon interposition or suspension-interposition arthroplasty had a significantly increased complication rate [25].
In a Cochrane Review from 2015, 11 studies with a total of 670 patients were included.
No difference could be found between the surgical treatment alternatives with pure trapeziectomy, trapeziectomy with suspension and/or interposition arthroplasty, spacer insertion, and TCMJ arthrodesis regarding patient satisfaction, pain, functional outcome, quality of life, and complication rate [28].