Bilateral subluxation of the base of the thumb secondary to an unusual abductor pollicis longus insertion: a case report

Bilateral subluxation of the trapeziometacarpal joint was related to abnormal insertion of the abductor pollicis longus (APL) tendon and an atrophic extensor pollicis brevis tendon. The APL tendon had four slips, all of which inserted into the fascia of the abductor pollicis brevis muscle distal and palmar to the trapeziometacarpal joint. Active pinch of the thumb resulted in subluxation of the trapeziometacarpal joint. To prevent reciprocal distal deformity, the proximal thumb was held in dynamic balance by attaching two slips of the APL tendon to the radiodorsal base of the first metacarpal. One tendon slip supplemented the tendon of the extensor pollicis brevis muscle. The lax capsule of the trapeziometacarpal joint was reinforced with the remaining tendon slip. The patient retains excellent bilateral function without subjective weakness after surgery.     

“Suspension plasty”: Trapeziometacarpal joint reconstruction using abductor pollicis longus

Painful arthrosis of the trapeziometacarpal joint (thumb basal joint) is the most common degenerative condition leading to dysfunction of the critical thumb ray. An arthroplastic reconstruction of this joint should be simple in concept, use only autogenous tissue, achieve pain relief, maintain thumb ray length and mobility at the metacarpal base, restore stability for power pinch and grasp function, and achieve predictable, reproducible long-term results. “Suspensionplasty,” as described in this report, has been used by the author since 1981. Initially, the technique was conceived as a method for salvaging failed silicone trapezium implant arthroplasties. Since 1982, Suspensionplasty has been used as the author's procedure of choice for trapeziometacarpal reconstruction of the thumb. It has proven to satisfy the above criteria for arthroplastic reconstruction.     

Problems with the metacarpophalangeal joint in the surgical treatment of osteoarthritis by inserting an ARPE type joint prosthesis

Progressive ankylosis of the trapeziometacarpal joint in flexion-adduction with closure of the first web in advanced trapeziometacarpal osteoarthritis gradually leads to compensatory dislocation of the metacarpophalangeal joint with hyperextension in the sagittal plane and abduction in the frontal plane. This deformity of the MP joint, initially reducible, but subsequently irreducible, results in the classical 'Z' deformity of the thumb in the sagittal plane. A less well known 'Z' deformity can also occur in the frontal plane due to distension of the medial collateral ligament. Surgical treatment of trapeziometacarpal osteoarthritis by arthroplasty must correct this secondary deformity of the MP joint to obtain an optimal result. The classical sagittal 'Z' deformity of the thumb can be easily corrected while this deformity is still reductible by releasing the fist metacarpal by tightening the abductor pollicis longus. When it is irreducible, this deformity can only be treated by MP arthrodesis, which contraindicates insertion of the ARPE trapeziometacarpal implant. Correction of the frontal 'Z' deformity of the thumb requires repair of the medial collateral ligament of the MP joint by ligamentorraphy (retightening) or ligamentoplasty.     

Pathomechanics of the thumb trapeziometacarpal joint

As the human thumb climbed the evolutionary ladder, the trapeziometacarpal joint was provided greater mobility at the expense of decreased bony stability. Soft tissue restraints were left to provide the primary stabilization of the thumb basal joint complex. Both degenerative and traumatic conditions compromise the function of these ligamentous structures and result in translational instability of the joint surfaces and secondary arthritic disease. Primary idiopathic osteoarthritis, Bennett's fracture-dislocation, and metacarpophalangeal hypermobility all impart a disturbance in biomechanics while extension metacarpal osteotomy, ligament reconstruction, and imposed metacarpophalangeal flexion mitigate these effects and improve trapeziometacarpal kinematics. As a compact joint amenable to en bloc resection, the trapeziometacarpal complex affords a unique opportunity to study the inter-relationship between biology and biomechanics in the pathogenesis of degenerative joint disease.     

Definition and classification of basal joint osteoarthritis. A critical analysis and proposals. Treatment options

Several definitions and classifications of basal joint osteoarthritis exist. Each of them can be criticized. The authors propose to define basal thumb osteoarthritis as osteoarthritis of the trapezometacarpal joint associated or not with lesions of scapho-trapezio-trapezoid and/or metacarpophalangeal joints. The proposed classification is derived from the Eaton-Littler classification. Stage O is identical to stage I of the Eaton-Littler classification: trapeziometacarpal instability without cartilage lesions. Stage I is osteoarthritis of the trapeziometacarpal joint only, without metacarpophalangeal deformity. Stage II is trapeziometacarpal osteoarthrites combined with reductible hyperextension deformity of the metacarpophalangeal joint. Stage III is trapeziometacarpal osteoarthrites combined with irreductible metacarpophalangeal deformity. Stage IV is identical to stage IV of the Eaton-Littler classification: combined trapeziometacarpal and scapho-trapezio-trapezoid osteoarthritis. The advantage of the proposed classification is that basal joint osteoarthritis is not only defined as real or potential (stage O) osteoarthritis of the trapeziometacarpal joint, but also includes precise evaluation of two other joints at the base of the thumb. This classification can be a guide for treatment options.     

Tendon interposition arthroplasty for degenerative arthritis of the trapeziometacarpal joint of the thumb

Arthrosis of the trapeziometacarpal joint of the thumb is a predictable sequelae of ligament laxity. A new technique of tendon interposition arthroplasty with ligament reconstruction using the flexor carpi radialis tendon for a painful arthritic trapeziometacarpal joint of the thumb is described. Twenty-one patients had 25 operative procedures; 14 were women and seven were men. All of the patients presented with intractable pain, crepitus, and varying degrees of laxity of the basal joint. Pinch strength was diminished. Follow-up averaged 37 1/2 months. After surgery, 91.7% of patients had good to excellent results, and 56% were completely pain free. Range of motion and grip and pinch strengths were equal on the operated and unoperated sides.     

Trapeziometacarpal joint instability affects the moment arms of thumb motor tendons

This study measured the changes in moment arm length of thumb motor tendons after simulated ligamentous instability and subsequent reconstruction of the trapeziometacarpal joint. Excursions of thumb motor tendons were measured simultaneously with the trapeziometacarpal joint angulation during flexion to extension and abduction to adduction motion. Tendon moment arms were calculated based on joint and tendon displacement techniques in the intact joint, after sequential sectionings of the capsuloligamentous restraints, and after the reconstruction procedure of Eaton and Littler. The results showed that moment arms of the abductor pollicis longus and extensor pollicis brevis tendons increased significantly as compared with those for normal joints during flexion to extension motion after sectioning the palmar capsuloligamentous components. After the ulnopalmar structures were cut, the moment arm of the extensor pollicis longus tendon had a statistically significant increase during abduction to adduction motion, and those of the extensor and flexor pollicis longus tendons decreased significantly during flexion to extension motion. Changed moment arms were restored to a normal level after the ligamentous reconstruction. These results indicate that ligamentous disruptions alter the mechanical balance of thumb motor tendons, which may contribute to joint deformities observed in trapeziometacarpal joint arthritis. Restoring joint stability is important to correct mechanical imbalance of the tendons.     

Total joint arthroplasty in the treatment of advanced stages of thumb carpometacarpal joint osteoarthritis

PURPOSE: Osteoarthritis of the thumb basal joint is a very common and disabling condition that frequently affects middle-aged women. Many different surgical techniques have been proposed for extensive degenerative arthritis of the first carpometacarpal (CMC) joint. Joint replacement has been an effective treatment of this condition. The purpose of this article is to present the outcome of a total cemented trapeziometacarpal implant in the treatment of more advanced stages of this disease. METHODS: Total joint arthroplasty of the trapeziometacarpal joint was performed on 26 thumbs in 25 patients to treat advanced osteoarthritis (Eaton and Littler stages III and IV) between 1998 and 2003. Indications for surgery after failure of conservative treatment were severe pain, loss of pinch strength, and diminished thumb motion that limited activities of daily living. A trapeziometacarpal joint prosthesis was the implant used in this series. The average follow-up time was 59 months. RESULTS: At the final follow-up evaluation, thumb abduction averaged 60 degrees and thumb opposition to the base of the small finger was present. The average pinch strength was 5.5 kg (85% of nonaffected side). One patient had posttraumatic loosening, which was revised with satisfactory results. Radiographic studies at the final follow-up evaluations did not show signs of atraumatic implant loosening. One patient complained of minimal pain, and the remaining 24 patients were pain free. CONCLUSIONS: In our series, total joint arthroplasty of the thumb CMC joint has proven to be efficacious with improved motion, strength, and pain relief. We currently recommend this technique for the treatment of stage III and early stage IV osteoarthritis of the CMC joint in older patients with low activity demands. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.     

Functional anatomy and biomechanics of the thumb.

The thumb is a mechanical unit consisting of strong ligaments and dynamic muscles, providing the resistance to the fingers and palm during pinch and grip. Each thumb joint has a mechanical equivalent that helps explain elements of thumb stability. The trapeziometacarpal joint is potentially the most unstable but has adapted to its unique position by special joint geometry and, in particular, a combination of support ligaments that permit a wide range of motion yet stability. New anatomic and mechanical studies demonstrate the key support structures that must be duplicated by reconstructive surgical procedures if thumb stability is to be maintained.     

Basal joint arthroplasty using the Roosevelt Hospital techniques

Many reconstructive procedures have been developed to treat osteoarthritis of the basal joint of the thumb. The current article describes techniques used at the Hand Surgery Center at Roosevelt Hospital in New York City. A tonometry applanation radiographic staging system is outlined; it serves as a rationale for selecting which form of arthroplasty is appropriate for a particular patient and is predicated on the extent of involvement of the trapezial articulations. Stage 1 disease implies symptomatic laxity of the trapeziometacarpal joint with normal articular surfaces and is most appropriately treated with volar ligament reconstruction. Stage 2 is an intermediate category and amenable to either volar ligament reconstruction or interpositional arthroplasty of the trapeziometacarpal joint, based on the condition of the articular cartilage at surgery. In stage 3 disease there are significant degenerative changes of the trapeziometacarpal joint with preservation of the articular surfaces of the scaphotrapezial joint. Two variations on ligament reconstruction with interpositional arthroplasty of the trapeziometacarpal joint are described; they have consistently good results. Finally, stage 4 is characterized by pantrapezial degenerative disease and necessitates trapezial resection. Reconstruction may be by silicone rubber implant arthroplasty using a stemmed trapezial implant stabilized by an abductor pollicis longus tenodesis. The alternative is a procedure in which the thumb metacarpal is tethered to the index metacarpal by a ligament reconstruction.     

Osteoarthritis at the base of the thumb.

Osteoarthritis at the base of the thumb is a functionally disabling condition and, as such, the basal joint complex represents the most commonly operated focus in the osteoarthritic upper extremity. Degenerative disease is predicted on instability of the trapeziometacarpal joint secondary to deterioration of the capsular and ligamentous restraints. Ligament reconstruction in the setting of a symptomatic hypermobile joint with intact cartilage surfaces may retard progression of arthritic disease. Complications related to silicone implant arthroplasty have given way to ligament reconstruction tendon interposition arthroplasty as the preferred procedure for the osteoarthritic thumb basal joint complex.     

Influence of metacarpophalangeal joint position on basal joint-loading in the thumb

BACKGROUND: Conventional wisdom holds that hyperextension of the metacarpophalangeal joint of the thumb is secondary to degenerative subluxation of the trapeziometacarpal joint as occurs in osteoarthritis. We propose that a hypermobile metacarpophalangeal joint may have a causative role in the development of primary osteoarthritis at the base of the thumb by concentrating forces on the palmar aspect of the trapeziometacarpal joint. METHODS: Twenty fresh-frozen cadaveric forearm specimens were obtained post mortem from donors with no history of connective-tissue disease. Each specimen was categorized by its passive range of metacarpophalangeal joint motion. Testing was conducted with Fuji ultra-low-pressure-sensitive film while the hand was in the lateral-pinch mode with the metacarpophalangeal joint in each of the following positions: unrestrained, pinned in neutral, pinned in 30 degrees of flexion, and pinned in maximal hyperextension. Quantitative analysis of the trapezial contact surface at each of the metacarpophalangeal joint positions was performed, and the center of pressure was determined. Each specimen was then classified according to the extent of arthritic disease (nonarthritic, moderately arthritic, or affected by end-stage arthritis). RESULTS: In specimens affected by end-stage osteoarthritis, the center of pressure on the trapeziometacarpal joint moved dorsally by 56.8% of the length of the trapezial surface with metacarpophalangeal joint flexions of 30 degrees (p < 0.01), whereas the corresponding values were 28.2% and 40.9% in the hyperextended and neutral metacarpophalangeal joint positions, respectively. In specimens with moderate osteoarthritis, 30 degrees of metacarpophalangeal joint flexion also produced the most dorsal trapeziometacarpal center of pressure (44.8%); however, this center of pressure was not significantly different from the centers of pressure at the other metacarpophalangeal joint positions. In nonarthritic specimens, the center of pressure was again significantly more dorsal with metacarpophalangeal joint flexion of 30 degrees than it was at the other positions (p < 0.01). CONCLUSION: Metacarpophalangeal joint flexion effectively unloaded the most palmar surfaces of the trapeziometacarpal joint regardless of the presence or severity of arthritic disease in this joint.     

Trapeziometacarpal total joint replacement using the Steffee prosthesis

The first forty-five Steffee trapeziometacarpal total joint replacements that were used to treat severe trapeziometacarpal arthritis in thirty-eight patients were analyzed retrospectively. The length of follow-up ranged from two through six and one-half years. Forty-two of the arthroplasties resulted in relief of pain, and the restoration of strength and motion was highly satisfactory. Although radiographs showed a high incidence of asymptomatic radiolucent lines at the bone-cement interface of the trapezial component, only three patients had symptomatic loosening. We concluded that trapeziometacarpal total joint replacement can provide good relief of pain and restore function of the thumb to patients with severe trapeziometacarpal arthritis, although further study is necessary to assess the long-term results of the procedure.     

A new surgical technique for the ligament reconstruction of the trapeziometacarpal joint

Isolated traumatic dislocation of the trapeziometacarpal joint is rare compared with fracture-dislocation of the joint. The mechanism of injury is usually axial loading on a flexed thumb metacarpal, leading to dorsal dislocation of the joint. Closed reduction with immobilization is an acceptable method of treatment if the joint is stable after the reduction. Otherwise, early ligamentous reconstruction is recommended to reduce the likelihood of secondary arthritis. Various surgical techniques have been used to reestablish the ligamentous integrity of the joint; however, these techniques usually reconstruct only 1 or 2 ligaments around the joint. The current technique is aimed to reconstruct all 4 ligaments of the trapeziometacarpal joint using a half strip of extensor carpi radialis brevis tendon.     

Traumatic thumb carpometacarpal joint dislocations

Isolated traumatic dislocation of the thumb carpometacarpal joint, also called the trapeziometacarpal joint, is a rare injury. Controversy still exists concerning which ligaments are the true key stabilizers for the joint and therefore need to be damaged to result in dislocation, and optimal treatment strategies for thumb carpometacarpal joint dislocations are the subject of continuing debate. We give a review of the literature concerning traumatic dislocations of the carpometacarpal joint of the thumb and propose a treatment algorithm.     

Kinematics of the trapeziometacarpal joint after sectioning of ligaments

This study was designed to examine the roles of ligaments in the maintenance of the articular kinematics of the trapeziometacarpal joint. Circumduction of the trapeziometacarpal joint was studied in 12 hands from fresh human cadavera. With use of a magnetic tracking system, changes in the motion of the base of the first metacarpal after ligament sectioning were analyzed and compared with those of the normal joint. Two sets of ligaments were sectioned: (a) the anterior oblique and ulnar collateral ligaments and (b) the first intermetacarpal ligament and the ulnar joint capsule. Sectioning of the anterior oblique and ulnar collateral ligaments resulted in a significant dorsal-ulnar shift in the path of the base of the first metacarpal. However, sectioning of the first intermetacarpal ligament did not affect the movement pattern of the center of the base. The anterior oblique and ulnar collateral ligaments provided constraint of the trapeziometacarpal joint during circumduction of the thumb.     

Contact area of the trapeziometacarpal joint.

Eighteen cadaver hands were studied to determine the contact area of the trapeziometacarpal joint by using silicone rubber casts. Casting material was introduced into the trapeziometacarpal joint during several motions of the thumb and the contact location was observed. The ratios of the contact area to the total joint area were calculated. The contact locations in opposition were the radial, volar, and ulnar segments of the trapezium and the dorsal, radial, and volar segments of the metacarpal. On average, 53% of the trapezium was in contact with 53% of the metacarpal in opposition, while 28% of the trapezium was in contact with 28% of the metacarpal in palmar abduction and 25% of the trapezium was in contact with 25% of the metacarpal in radial abduction. The contact area was the largest in opposition. The trapeziometacarpal joint is stable in opposition and facilitates a strong pinch.     

In vivo kinematics of the first carpometacarpal joint after trapezectomy

First carpometacarpal osteoarthitis is frequent and surgery may be necessary if medical treatment is not efficient. Trapeziometacarpal arthroplasty, trapeziometacarpal arthrodesis and trapezectomy may be proposed. These surgical solutions may modify the carpometacarpal kinematics of the thumb. However, no clinical tools are currently available to assess these modifications. The goal of our study is to assess the TM kinematics, with an optoelectronic system, in patients after trapezectomy. Ten women, average age 53 (range 45 to 67) underwent trapezectomy with ligamentoplasty for trapeziometacarpal osteoarthritis. An optoelectronic device (Polaris(?)) was used to analyse postoperative range-of-motion of the thumb. Splints were used in order to isolate the trapeziometacarpal joint and retroreflective markers were placed both on the splints and on the thumb. Mean flexion-extension, abduction-adduction, axial rotation and circumduction were calculated. RESULTS: The mean range-of-motion of trapeziometacarpal joint was 50 degrees for flexion-extension, 47 degrees for abduction-adduction and 11 degrees for axial rotation. The mean angle between rotation axes was 90 degrees and the mean distance d between the axes was 3 millimeters. Comparisons between patients and healthy subjects showed no significant differences in flexion-extension, abduction-adduction and axial rotation. Circumduction in patients was reduced compared to healthy subjects. No significant differences were noted between the operated side and the contralateral side. DISCUSSION AND CONCLUSION: Our study showed that this protocol can be used in the postoperative follow-up of patients after trapezectomy. We did not find any significant differences compared to the contralateral side. However, circumduction after trapezectomy was reduced compared to healthy subjects.     

Fractures at the base of the thumb: treatment with oblique traction.

Oblique traction on the thumb metacarpal, originally described for the treatment of Bennett's fracture, has been applied to comminuted intra-articular fractures of the thumb metacarpal to counter the forces that cause shortening and varus angulation. It also has been applied to fractures of the trapezium to restore congruity of the trapeziometacarpal joint. It was successful in achieving and maintaining a satisfactory reduction in eight patients with these three types of fractures.