Anatomie et physiologie de l’articulation trapézométacarpienne humaine

Is increased trapezial slope a cause of early trapeziometacarpal osteoarthritis?

OBJECTIVES

Thumb carpometacarpal joint osteoarthritis is one of the most common forms of osteoarthritis in the hand. The underlying causes are multifactorial. We investigated whether increased trapezial slope could be a causal factor.

MATERIAL AND METHODS

We measured trapezial slope and 1st metacarpal slope in 37 patients with early thumb carpometacarpal joint osteoarthritis and compared results with 41 patients without osteoarthritis, using computer-supported 3D-analysis based on CT scans.

RESULTS

There was a significant intergroup difference in trapezial slope (111° in patients with osteoarthritis, and 107° in patients without) and in 1st metacarpal slope (17° versus 14°).

CONCLUSION

Steeper trapezial slope seemed to be a risk factor for thumb carpometacarpal joint osteoarthritis. Therefore, correction of trapezial slope by trapezium osteotomy could be a valuable surgical approach in early thumb carpometacarpal joint osteoarthritis.

Addition-Subtraction Osteotomy With Ligamentoplasty for Symptomatic Trapezial Dysplasia With Metacarpal Instability: A 10-Year Follow-Up

PURPOSE

Symptomatic trapezial dysplasia with metacarpal instability in a nonarthritic joint can lead to a disabling condition characterized by decreased pain, mobility, and strength. Bony correction may be required in dysplastic joints, because soft tissue correction might be insufficient to stabilize the trapeziometacarpal (TMC) joint. We combined 2 techniques described previously, an abduction-extension osteotomy of the first metacarpal and an opening wedge osteotomy of the trapezium, including a ligament reconstruction (hemi-flexor carpi radialis). The aim of this study was to investigate the long-term results of this technique.

METHODS

In this single-center, retrospective cohort study, we included patients treated surgically for primary instability of the TMC joint with trapezial dysplasia between 2003 and 2007. We measured pain (visual analog scale), mobility (opposition and retropulsion), patient-reported disability (Quick-Disabilities of the Arm, Shoulder, and Hand), and radiographic evaluation (Devers' angle) 10 years after surgery. Results were compared with preoperative data.

RESULTS

We reviewed 17 thumbs retrospectively (mean follow-up, 12 years). One patient was converted to a TMC prosthesis. Key pinch improved significantly from 5.2 kg (±2.4 kg) at baseline to 6.3 kg (±2.1 kg) at 10-year follow-up. Quick-Disabilities of the Arm, Shoulder, and Hand score and Devers' angle were significantly better after 10 years compared with preoperative data. There was a mean visual analog scale score of 0.5 (±1.4) at rest and 2.3 (±2.6) during activities. Ten years after surgery, 5 patients had a stable Eaton score of 1. Four patients had progression to stage 2, and 5 to stage 3.

CONCLUSIONS

Addition-subtraction osteotomy with ligamentoplasty has a positive long-term effect on symptomatic trapezial dysplasia with TMC joint instability. Although this operation did not protect the TMC joint from further wear, pain was acceptable for most patients.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Radial and palmar active range of motion measurement: reliability of six methods in healthy adults

The current study aims to assess the reliability of 6 range-of-motion measurement methods for the thumb carpometacarpal joint: Pollexograph-thumb, Pollexograph-metacarpal, radius-metacarpal goniometry, intermetacarpal goniometry, intermetacarpal distance, and thumb-distal-interphalangeal distance. A senior hand surgeon, an experienced resident, and a less experienced research fellow evaluated the dominant hands of 29 healthy subjects. All 6 methods were performed for radial adduction, radial abduction, and palmar abduction, but only distance methods were measured for palmar adduction. Intrarater and interrater reliability were computed using intraclass correlation coefficient, standard error of measurement, and smallest detectable difference. Pollexograph-thumb method showed the highest active range of movement for radial adduction (12°) and abduction (71°), while all the other angular methods resulted in approximately 20° for radial adduction and 50° for radial abduction. Distance methods showed comparable mean results for radial and palmar range of motion (adduction/abduction): intermetacarpal distance (50 mm/60 mm) and thumb-distal-interphalangeal distance (50 mm/120 mm). Interrater reliability using the results of the intraclass correlation coefficient demonstrates that Pollexograph-thumb and Pollexograph-metacarpal showed excellent reliability for radial adduction and abduction, whereas Pollexograph-thumb method revealed the best reliability for palmar abduction. Moreover, thumb-distal-interphalangeal distance also showed excellent reliability for radial and palmar abduction. Conventional goniometry showed a large variety of reliability results, ranging from poor to excellent. No clinical benefit can be derived from assessing the palmar adduction. We found that the Pollexograph-thumb showed excellent reliability results throughout all measurements. Thumb-distal-interphalangeal-joint distance is especially valuable for assessing radial and palmar abduction.

Minimum 10-year clinical and radiological follow-up of trapeziectomy with interposition or suspensionplasty for basal thumb arthritis

HYPOTHESIS

The aim of this article is to analyze clinical and radiological outcomes of trapeziectomy performed for basal thumb arthritis after a minimum follow-up of 10 years to gain further insight from shorter and medium-term studies reporting satisfactory evolution.

METHODS

We reviewed 67 trapeziectomies, operated on by the same senior surgeon after a minimum follow-up of 10 years. The sample included 16 cases of suspensionplasty and 51 interpositions. Clinical outcome evaluated strength, pain, joint amplitude, Kapandji opposition score, Disabilities of the Arm, Shoulder and Hand score, complications and revision surgery. Radiological evaluation criteria included osteoarthritis and collapse of the trapezial void.

RESULTS

After a 10-year follow-up, clinical results remained stable despite radiological degradations. Long-term clinical outcomes of trapeziectomy for basal thumb arthritis are very positive, with interpositioning as an isolated procedure appearing, clinically, to be the preferred treatment despite greater radiological degradation when compared to suspensionplasty.

CONCLUSION

In addition to offering insight into minimum 10-year follow-up, this study also pinpoints this paradoxical dissociation of clinical-radiological outcomes.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic III.

Addition-subtraction osteotomy with ligamentoplasty for symptomatic trapezial dysplasia with metacarpal instability

Trapeziometacarpal instability with trapezial dysplasia is a disabling condition long before the radiological changes of osteoarthritis appear. In dysplastic joints surgical soft tissue correction fails to prevent the instability, requiring a correction of the bony anatomy. We combined two techniques described in the past, an abduction osteotomy of the first metacarpal and an opening wedge osteotomy of the trapezium, to which we added a ligament reconstruction. The combination of both osteotomy techniques restores the anatomy and centres the forces acting across the joint. We have done this procedure 21 times since 2003 in 18 patients. Seventeen thumbs were reviewed prospectively with a mean follow-up of 39 (range 16-65) months. Mean QuickDASH improved by 33.9 points, the key pinch improved by 1.8 kg and the grip strength improved by 8.7 kg. The visual analogue scale for pain improved from 7.9 preoperatively to 2 postoperatively. This technique preserves the trapeziometacarpal joint, allowing other techniques to be used if painful arthritis should develop in the middle to long term.

[Partial trapezectomy with suspension and interposition tendinoplasty for trapezometacarpal osteoarthritis: 5 years results]

OBJECTIVES

Partial trapezectomy with suspension and interposition tendinoplasty is an alternative to total trapezectomy or trapezometacarpal arthroplasty for the treatment of trapezometacarpal osteoarthritis. This technique preserves the thumb length allowing good motion and satisfactory pollicidigital strength. The purpose of the present study is to report our experience with this procedure reviewing a continuous monocentric series of 41 thumbs with an averaged follow-up of 5 years. Surgical technique, clinical and radiographic results, and indications are discussed.

METHODS

Thirty-three patients (41 thumbs) of 57.4 years average age underwent this procedure. According to Dell classification there were 23 stage II, 15 stage III, and 3 stage IV. No sign of osteoarthritis of the scapho-trapezo-trapezoidal joint were noted. Clinical and radiographic evaluations were available for all the patients. Pollicidigital strength was measured with a dynamometer.

RESULTS

At 57 months average follow-up, 71% of the patients had no pain. Average opposition was 9.56 out of 10 according to Kapandji, the key pinch was equal to 6.51 kg, and M1M2 space was 34 degrees . Trapezometacarpal space was 2.52 mm on average. There were only 3 complications related to a reflex sympathetic dystrophy.

CONCLUSION

Partial trapezectomy with tendinoplasty gives satisfactory functional results which is maintained with follow-up. It allows recovery of a functional pollicidigital strength by limiting thumb shortening. It is a reliable procedure with a low rate of complication indicated for isolated thumb trapezometacarpal joint osteoarthritis without scapho-trapezo-trapezoidal joint involvement.

Traitement des dysplasies trapéziennes symptomatiques instables par ostéotomie d'addition–soustraction et ligamentoplastie

INTRODUCTION

Trapezometacarpal instability with trapezial dysplasia is an incapacitating condition long before radiological changes appear. Most of the patients are young and demanding. Treatment is often conservative. Surgical treatment options are relatively classic, starting with a ligamentoplasty of the base of the first metacarpal or a tenotomy of the transarticular accessory slip of the abductor pollicis longus. Other options such as arthrodesis and arthroplasty have not been so successful in this situation.

METHOD

The idea arose to combine two techniques described previously. In 1973 Wilson published his technique of abduction osteotomy of the first metacarpal as a treatment for basal osteoarthritis of the thumb. In 2002, Kapandji and Heim published their opening wedge osteotomy of the trapezium in order to correct the slope of a dysplastic trapezium. The combination of both of these techniques avoids closing of the first web by utilising the abduction osteotomy of the first metacarpal. Moreover, the opening wedge osteotomy corrects the dysplastic lateral rim of the trapezium by correcting its slope.

RESULTS

We have been performing this technique since 2001 and 2005 in six patients. The preliminary results are encouraging, 5 of them were able to resume their work. A fair result was achieved in a young patient.

DISCUSSION

The described technique is relatively easy and has the advantage of preserving the trapezometacarpal joint. In addition, it leaves the door open for other techniques if it eventually should fail in the long term.

[The trapezio-metacarpal joint: the strain of the ligaments as a function of the thumb position. Study on an enlarged model]

INTRODUCTION

The aim of this paper was to develop an enlarged anatomical model of the trapezio-metacarpal joint in order to measure the strains on the ligaments when this joint was passively moved in several directions under constant loading.

MATERIAL AND METHOD

A model of the two first rays of the hand was made in polystyrene, at a X3 enlargement, and the ligaments substituted by rubber bands with well characterized mechanical properties so as to reproduce the actual ratio of stiffness (approximately = 10) of the different tissues (bones and ligaments) found in real life. The first metacarpal was moved in 6 directions as described by Ebskov (1970) and Pieron (1973, 1980) using a small spring exerting a constant force (1.5 N) tilted at 30 degrees with respect to the transverse plane. The strain was measured between two white marks for each model ligament and each direction respectively, and the percentage of lengthening was calculated. A statistical study was performed using the non-parametrical Test of Wilcoxon in order to compare the ligament strains obtained in the different directions of loading.

RESULTS

The largest strains were observed in the intermetacarpal ligament and in the anterior oblique ligament reaching 26 to 39% in direction J (posteromedial) and in direction L (posterolateral). Deformations of the two parts of the dorsoradial ligament and of the posterior oblique ligament were equal or inferior to 12% and were observed in the other 4 directions: D, F, K, I (Anterolateral, maximal anteposition, anteromedial, medial) and their combinations.

CONCLUSION

. These data may be useful for helping the understanding of the biomechanics of the basal joint of the thumb. Nevertheless, we are dealing here with a simplified model, which must be considered with caution if the results are to be applied to the living joint.