Trapezium Tunnel Syndrome.

The trapezium tunnel is situated on the lateral side of the carpal tunnel, lined with synovial tissue, and accommodates the flexor carpi radialis tendon. Trapezium tunnel syndrome is characterized by flexor carpi radialis tendinitis/peritendinitis and may lead to complicated clinical scenarios, such as flexor carpi radialis tendon rupture and the formation of primary or recurrent ganglion cysts on the volar radial side of the wrist and thenar area. Notably, the simultaneous presence of trapezium tunnel syndrome might contribute to unsuccessful outcomes in carpal tunnel surgeries. Trapezium tunnel syndrome may arise from either intrinsic or extrinsic factors. The entity of trapezium tunnel syndrome has attracted a low index of clinical suspicion because the other causes of radial side wrist pain that are more prevalent and frequent. We present a narrative review of this condition in an endeavor to heighten awareness and clinical suspicion of trapezium tunnel syndrome.

Three-Dimensional Analysis of the Trapezium Subchondral Bone and its Association with Trapeziometacarpal Joint Osteoarthritis.

Subchondral bone properties are associated with the pathogenesis of osteoarthritis (OA), but this relationship has not been confirmed in the trapeziometacarpal joint (TMCJ). We aimed to evaluate the thickness (SBT) and density (SBD) of three-dimensional (3D) trapezium subchondral bone models derived from computed tomography (CT) images, and their relationships with early-stage TMCJ OA. We reviewed patients with a distal radius fracture who underwent conventional CT scans and such osteoporosis evaluations as bone mineral density (BMD) and bone turnover markers (BTMs). From 3D trapezium subchondral bone models, we measured SBT and SBD according to the OA stage and performed multivariate analyses to evaluate their associations with age, sex, body mass index, BMD, and BTMs. As results, a total of 156 patients (78 men and 78 age-matched women; mean age, 67 ± 10 years) were analyzed. There were 30 (19%) with grade 0, 71 (45%) with grade 1, 13 (8%) with grade 2, and 42 (27%) with grade 3 TMCJ OA. SBT was significantly lower in patients with grade 1 OA than those with grade 0 or grade 3 OA, but SBD generally increased according to the OA severity. Low SBT was associated with low BMD, and low SBD with low BMD, high osteocalcin levels, and severe OA grades. In conclusion, patients with early-stage radiographic TMCJ OA have a lower SBT at the trapezium, which may support the potential role of subchondral bone in OA pathogenesis. This study also shows that subchondral bone properties are associated with BMD and osteocalcin levels.

[Hemitrapeziectomy of the carpometacarpal joint of the thumb]. / Hemiresektionsarthroplastik am Daumensattelgelenk.

BACKGROUND: Hemiresection arthoplasty or partial trapeziectomy of the carpometacarpal joint of the thumb is a surgical option in stages 1-3 according to Eaton-Littler classification. Preservation of the intact scaphotrapeziotrapezoidal (STT) joint and maintenance of the length of the thumb is the advantage of this technique. TECHNIQUE: Technically, partial trapeziectomy is only slightly more complex compared to trapeziectomy with or without suspension. An interposition of autologous or allogeneic material is recommended; suspension arthroplasty is also possible in almost all common variants. Despite these theoretical advantages, this technique has not proven advantageous in practice, neither in terms of function nor in terms of time, compared to other techniques. The great advantage of partial trapeziectomy, however, is the wide range of options for revision surgery in the case of persistent complaints. RESULTS: The risk of proximalization of the thumb due to an inadequate interposition is generally minor and is usually caused by implant sintering. This can easily be compensated for by implanting a larger graft. Persistent instabilities are the most common cause of persistence of symptoms and can usually be remedied by autologous or allogeneic suspension arthroplasty. In addition, the entire range of endoprosthetics is also possible with a previous spare resection of the trapezium and the possibility of a complete trapeziectomy remains in any case. The obvious theoretical advantages of arthroscopic hemitrapeziectomy need to be confirmed in practice in future.

[Minimally invasive procedures in the early stages of trapeziometacarpal joint osteoarthritis : Denervation, arthroscopy and autologous fat transplantation]. / Minimal-invasive Verfahren im Frühstadium der Daumensattelgelenksarthrose : Denervierung, Arthroskopie, autologe Fetttransplantation.

BACKGROUND: Resection arthroplasty of the trapezium with or without tendon interposition is the standard procedure in the treatment of advanced, symptomatic thumb carpometacarpal joint osteoarthritis. Treatment recommendation in the early stages without visible or minimal radiographic changes is often difficult, especially when conservative treatment methods have already been exhausted. In these cases, there is the possibility of the minimally invasive methods of denervation, arthroscopic procedures and autologous fat transplantation. OBJECTIVES: Which minimally invasive procedures are available for the treatment of thumb carpometacarpal joint osteoarthritis and how is their value to be assessed? METHODS: The minimally invasive methods of denervation, arthroscopic procedures and autologous fat transplantation for the treatment of thumb carpometacarpal joint osteoarthritis are described and current results from the literature are discussed. RESULTS: Good results have been reported with all three procedures. However, the reports are almost exclusively based on retrospective studies with small numbers of patients, which lack control groups, so the results cannot be regarded as definitive. CONCLUSIONS: Denervation, arthroscopic procedures and autologous fat transplantation appear to be suitable methods in the early stages of thumb carpometacarpal joint osteoarthritis. Further studies, especially comparative randomised trials that report medium and long-term results, would allow further assessment of these methods.

Osteosarcoma of the Trapezium.

Osteogenic sarcoma is a malignant tumor that rarely affects the hand. When it does, it most often involves the phalanges or metacarpal heads. We present the case of a 51-year-old woman with a low-grade osteosarcoma affecting the trapezium bone of her left hand. A total trapeziectomy with partial removal of the first metatarsal, scaphoid, trapezoid, and capitate bones was performed, and no adjuvant therapy was administered. Six years after the intervention, the patient is disease-free, with excellent functionality and yearly imaging tests showing no signs of recurrence.

Cartilage wear patterns in severe osteoarthritis of the trapeziometacarpal joint: a quantitative analysis.

OBJECTIVE: The present quantitative study aimed to assess the three-dimensional (3-D) cartilage wear patterns of the first metacarpal and trapezium in the advanced stage of osteoarthritis (OA) and compare cartilage measurements with radiographic severity. DESIGN: Using 19 cadaveric trapeziometacarpal (TMC) joints, 3-D cartilage surface models of the first metacarpal and trapezium were created with a laser scanner, and 3-D bone surface model counterparts were similarly created after dissolving the cartilage. These two models were superimposed, and the interval distance on the articular surface as the cartilage thickness was measured. All measurements were obtained in categorized anatomic regions on the articular surface of the respective bone, and we analyzed the 3-D wear patterns on the entire cartilage surface. Furthermore, we compared measurements of cartilage thickness with radiographic OA severity according to the Eaton grading system using Pearson correlation coefficients (r). RESULTS: In the first metacarpal, the cartilage thickness declined volarly (the mean cartilage thickness of the volar region was 0.32 ± 0.16 mm, whereas that of the dorsal region was 0.53 ± 0.18 mm). Conversely, the cartilage evenly degenerated throughout the articular surface of the trapezium. Measurements of the categorized regions where cartilage thinning was remarkable exhibited statistical correlations with radiographic staging (r = -0.48 to -0.72). CONCLUSIONS: Our findings indicate that cartilage wear patterns differ between the first metacarpal and trapezium in the late stage of OA. There is a need for further studies on cartilage degeneration leading to symptomatic OA in the TMC joint.

Predicting Outcome After Hand Orthosis and Hand Therapy for Thumb Carpometacarpal Osteoarthritis: A Prospective Study.

OBJECTIVES: (1) To identify predictive factors for outcome after splinting and hand therapy for carpometacarpal (CMC) osteoarthritis (OA) and to identify predictive factors for conversion to surgical treatment; and (2) to determine how many patients who have not improved in outcome within 6 weeks after start of treatment will eventually improve after 3 months. DESIGN: Observational prospective multicenter cohort study. SETTING: Xpert Clinic in the Netherlands. This clinic comprises 15 locations in the Netherlands, with 16 European Board certified (FESSH) hand surgeons and over 50 hand therapists. PARTICIPANTS: Between 2011 and 2014, patients with CMC OA (N=809) received splinting and weekly hand therapy for 3 months. INTERVENTION: Not applicable. MAIN OUTCOME MEASURES: Satisfaction and pain were measured with a visual analog scale and function with the Michigan Hand Questionnaire at baseline, 6 weeks, and 3 months posttreatment. Using regression analysis, patient demographics and pretreatment baseline scores were considered as predictors for the outcome of conservative treatment after 3 months and for conversion to surgery. RESULTS: Multivariable regression model explained 34%-42% of the variance in outcome (P<.001) with baseline satisfaction, pain, and function as significant predictors. Cox regression analysis showed that baseline pain and function were significant predictors for receiving surgery. Of patients with no clinically relevant improvement in pain and function after 6 weeks, 73%-83% also had no clinically relevant improvement after 3 months. CONCLUSION: This study showed that patients with either high pain or low function may benefit most from conservative treatment. We therefore recommend to always start with conservative treatment, regardless of symptom severity of functional loss at start of treatment. Furthermore, it seems valuable to discuss the possibility of surgery with patients after 6 weeks of therapy, when levels of improvement are still mainly unsatisfactory.

Trapezium fracture: a common clinical mimic of scaphoid fracture.

PURPOSE: Fractures of the trapezium are rarely diagnosed on plain radiographs after acute wrist trauma. High-resolution cross-sectional imaging identifies fractures of the trapezium as the most common radiographically occult carpal bone fracture. We review the fracture frequency, mechanisms and patterns of trapezium fractures. METHODS: Cone beam CT was performed in patients with suspected radiographically occult radiocarpal fracture following acute injury. The frequency of carpal bone fractures was assessed and compared. RESULTS: Ninety-three radiographically occult wrist fractures were identified in 166 patients with acute trauma and negative radiographs. The trapezium was the most frequently fractured carpal bone, making up 20.4% of wrist fractures. Seventy-nine percent of trapezium fractures involved the volar ridge. The scaphoid was the clinically suspected fractured bone at initial assessment in 84% of patients with trapezium fractures. CONCLUSION: Fractures of the trapezium in acute wrist trauma are much more common than described in the literature. If initial radiographs are negative, a fracture of the trapezium is more likely to be present than one of the scaphoid, despite high levels of clinical suspicion for scaphoid injuries. Awareness of the types and mechanisms of trapezium fracture is important. Cross-sectional imaging should be considered in all cases of post-traumatic wrist pain with negative radiographs.

Unusual cause of the thumb basal joint pain: osteoid osteoma of the trapezium.

The trapezium is rare site of osteoid osteoma development. The diagnostic challenge lies in its rare occurrence, and requires differentiation from various disease entities causing thumb basal joint pain. We report the case of a 29-year-old male who presented with severe thumb basal joint pain. He was initially treated for calcific periarthritis because of concomitant calcifications around the thumb basal joint, but had undiscovered osteoid osteoma. A high index of suspicion to a patient with wrist pain unresponsive to prior treatment is necessary for diagnosis of osteoid osteoma.

Morphology and Mobility of the Reconstructed Basilar Joint of the Pollicized Index Finger.

PURPOSE: To evaluate outcome and function of the reconstructed basilar thumb joint after index finger pollicization in patients presenting congenital thumb deficiency. METHODS: Plain radiographs and 4-dimensional dynamic volume computed tomography scan were used to evaluate the outcome of 23 pollicizations performed on 14 children between 1996 and 2009. The mean follow-up was 8 years. Patients performed continuous movements of thumb opposition during the imaging studies. Four-dimensional scan images made it possible to visualize mobility within the reconstructed joint. RESULTS: In 14 cases, union occurred in the metacarpal head/metacarpal base interface. In the 9 other cases, there was a nonunion at this interface. The reconstructed joint was mobile in 20 cases, including 3 in which there was also mobility at the site of the nonunion. In 3 cases in our series, mobility was present only at the site of the nonunion, between the base and the head of the second metacarpal. Remodeling and flattening out of the metacarpal head occurred in 16 of 23 cases. The transposed metacarpal head remained spherical in 7 cases. CONCLUSIONS: The reconstructed joint adapts, both morphologically and functionally, allowing movement on all 3 spatial planes. Existing mechanical constraints on the reconstructed joint may explain its remodeled appearance. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Chondrogenic capability of osteoarthritic chondrocytes from the trapeziometacarpal and hip joints.

Osteoarthritis is the most common degenerative disease of joints like the hip and the trapeziometacarpal joint (rhizarthrosis). In this in vitro study, we compared the chondrogenesis of chondrocytes derived from the trapezium and the femoral head cartilage of osteoarthritic patients to have a deeper insight on trapezium chondrocyte behavior as autologous cell source for the repair of cartilage lesions in rhizarthrosis. Chondrocytes collected from trapezium and femoral head articular cartilage were cultured in pellets and analyzed for chondrogenic differentiation, cell proliferation, glycosaminoglycan production, gene expression of chondrogenic and fibrous markers, histological and immunohistochemical analyses. Our results showed a higher cartilaginous matrix deposition and a lower fibrocartilaginous phenotype of the femoral chondrocytes with respect to the trapezium chondrocytes assessed by a higher absolute glycosaminoglycan and type II collagen production, thus demonstrating a superior chondrogenic potential of the femoral with respect to the trapezium chondrocytes. The differences in chondrogenic potential between trapezium and femoral head chondrocytes confirmed a lower regenerative capability in the trapezium than in the femoral head cartilage due to the different environment and loading acting on these joints that affects the metabolism of the resident cells. This could represent a limitation to apply the cell therapy for rhizoarthrosis.

A comparative study of diagnostic and imaging techniques for osteoarthritis of the trapezium.

OBJECTIVES: The aims of this study were to determine whether micro-CT is a reliable investigation method to evaluate the severity of OA in the trapezium and to develop a novel micro-CT scoring system based on a quantitative assessment of the subchondral bone thickness in order to better assess OA through an objective parameter. METHODS: We compared different diagnostic and imaging techniques performed consecutively on each sample: X-ray, visual analysis, micro-CT and histology. OA and healthy trapezia were subjected to semi-quantitative and quantitative analyses to be classified in four degrees of severity in OA (control, OA-2, OA-3 and OA-4). Specifically, samples were analysed using Dell's score for X-ray, Brown's score for visual analysis and Mankin's score for histology. Micro-CT was scored using a novel quantitative scoring system based on subchondral bone thickness measurements. Results obtained with each technique were then compared and correlated. RESULTS: X-ray analysis showed a higher frequency of OA-2 (27%) and OA-3 (32%) compared with OA-4 (5%), whereas visual analysis, micro-CT and histology showed a lower percentage for OA-2 (18%, 18% and 14%) and OA-3 (23%) and increased frequency for OA-4 (45%, 32% and 40%). Only the micro-CT score of subchondral bone thickness correlated significantly with all the other techniques (P < 0.05). CONCLUSION: This is the first comparison of techniques proposing a novel scoring system based on objective and quantitative micro-CT data that can be applied as a useful diagnostic tool for OA, providing a deeper comprehension of the pathophysiology of OA in trapezium.

Trapeziectomy With a Tendon Tie-in Implant for Osteoarthritis of the Trapeziometacarpal Joint.

PURPOSE: To evaluate the early to mid-term clinical and radiological outcomes of trapeziectomy with a tendon tie-in trapezium implant arthroplasty for moderate to severe trapeziometacarpal (TMC) joint osteoarthritis (Eaton stages III to IV). METHODS: We assessed all patients who underwent trapeziectomy and tendon tie-in trapezium implant arthroplasty stabilized with a Weilby flexor carpi radialis tendon sling for osteoarthritis of the TMC joint between 2008 and 2010 at our institution. Twenty-two patients (28 thumbs) who had had an operation at least 12 months earlier were clinically evaluated at an average follow-up of 18 months. Subjective clinical outcomes evaluation included visual analog scale scores and Disabilities of the Arm, Shoulder, and Hand score questionnaires. Objective clinical evaluation included lateral pinch and grip tests and active thumb range of motion. All patients underwent a radiological assessment by 2 independent musculoskeletal radiologists. In cases of unilateral treatment, we compared clinical results obtained from the operated hands with the contralateral hand. RESULTS: The mean preoperative visual analog scale score of the cohort was 7.4. We documented a statistically significant improvement to 1.2 at a mean of 18 months after the operation (range, 12-26 mo). The mean postoperative Disabilities of the Arm, Shoulder, and Hand score was 21. Thumb palmar abduction was 85°; thumb metacarpophalangeal joint flexion and TMC joint extension were 30° and 10°, respectively. There were 2 cases of prosthesis removal owing to implant dislocation. No late complications were recorded. CONCLUSIONS: Good short-term to mid-term results and stability of TMC arthroplasty implant can be achieved with tie-in trapezium implant stabilized with a Weilby flexor carpi radialis tendon sling. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Stability of the Basal Joints of the New Thumb After Pollicization for Thumb Hypoplasia.

PURPOSE: To investigate the presence or absence of union of the new trapezium to the retained metacarpal base after pollicization and to relate this to stability of the new trapezium and the new carpometacarpal joint. METHODS: Thirty-six patients (46 pollicizations) were assessed at clinical review. Mean time from surgery to review was 96 months (range, 9-260 mo). Clinical assessment measured range of motion (ROM) at the carpometacarpal joint, stability of the carpometacarpal joint, and extrinsic and intrinsic strength of both hands. Radiological review evaluated 3 parameters: bony union between the new trapezium and retained metacarpal base, stability of the new trapezium in relationship to the metacarpal base, and carpometacarpal joint stability. RESULTS: There was radiographic nonunion between the new trapezium and the retained metacarpal base in 8 (1 treated) of 46 pollicizations. Relative risk of instability of the new trapezium was 39 times more likely if nonunion was present. Nine pollicizations were unstable at the carpometacarpal joint, 8 in those with union and 1 with nonunion. Relative risk of instability was 1.4 times more likely for those with union. For patients with nonunion, ROM and grip strength variables were reduced but only grip strength reached statistical significance. In patients with carpometacarpal joint instability, ROM and grip strength variables were reduced but none of the variables reached statistical significance. CONCLUSIONS: This study suggests that when the surgeon is attempting to obtain union of the new trapezium to the retained metacarpal base, failure to do so results in a poorer thumb with a significantly increased risk of trapezial instability and decreased grip strength. There is a mildly increased risk of carpometacarpal joint instability with union, but significantly poorer function as a consequence of this has not been demonstrated. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Carpal fractures.

Carpal fractures are exceedingly rare clinical entities and are often associated with concomitant injuries. In this review, we focus on fractures of the carpus, excluding the scaphoid, and provide an update on the current consensus as to mechanism, diagnosis, management, outcomes, and complications after such injuries.

Sonography of trapezial ridge fractures.

Trapezial ridge fractures are very rare. These can be a diagnostic challenge and one needs to have a high index of suspicion. We report two cases of trapezial ridge fractures that were diagnosed sonographically and confirmed by cross-sectional imaging (CT or MRI).

Does trapezium remodeling correlate with cup shape?

We investigated whether trapezium bone reaction was different following implantation of a trapeziometacarpal total joint replacement with a hemispheric or a conical cup. Fifty-three Keri Medical Touch implants with hemispheric cup and 53 with conical cup were prospectively followed up radiographically. We compared radiographs taken immediately and one year after surgery for cup subsidence, tilt, heterotopic ossification and loosening. Cup subsidence of at least 1 mm was detected in 4% of cases for both cup types. Additive bone reaction around the cup of more than 1 mm was present in 62% of conical cups and 47% of hemispheric cups. These were minor and there were no large ossifications with risk of impingement. Minor radiolucency was seen superficially at the implant-bone interface of 13% of the hemispheric cups and 9% of the conical cups. None of these bone reactions differed significantly according to cup design.

Influence of the anatomy of the proximal articular surface of the trapezium (PAST) and the trapezoidal articular surface of the trapezium (TRAST) in cup placement during trapeziometacarpal arthroplasty.

The influence of the anatomy of the proximal articular surface of the trapezium (PAST) and the trapezoidal articular surface of the trapezium (TRAST) on cup placement during trapeziometacarpal arthroplasty was retrospectively evaluated on 56 preoperative anteroposterior radiographs of patients who underwent surgery for trapeziometacarpal osteoarthritis. The percentage coverage of the prosthetic cup by the PAST and the available height of the trapezium were calculated. In 39% of cases, there was a significant difference (up to a mean 4.5 mm, p < 0.001) between the radial height of the trapezium (which is usually considered) and the available height of the trapezium. The anatomy of the PAST and the TRAST has an impact on the placement of the prosthetic cup when trapezium height is low. The results of the present study suggest that these considerations must be known by all operators performing trapeziometacarpal arthroplasty; that lateralization, implant suspension, or surgical alternatives should be considered to prevent several intra- and postoperative surgical complications. Level of evidence: IV.

Development of an implantable trapezium carpal bone replacement for measuring in vivo loads at the base of the thumb.

Understanding the loads that occur across musculoskeletal joints is critical to advancing our understanding of joint function and pathology, implant design and testing, as well as model verification. Substantial work in these areas has occurred in the hip and knee but has not yet been undertaken in smaller joints, such as those in the wrist. The thumb carpometacarpal (CMC) joint is a uniquely human articulation that is also a common site of osteoarthritis with unknown etiology. We present two potential designs for an instrumented trapezium implant and compare approaches to load calibration. Two instrumented trapezia designs were prototyped using strain gauge technology: Tube and Diaphragm. The Tube design is a well-established structure for sensing loads while the Diaphragm is novel. Each design was affixed to a 6-DOF load cell that was used as the reference. Loads were applied manually, and two calibration methods, supervised neural network (DEEP) and matrix algebra (MAT), were implemented. Bland-Altman 95% confidence interval for the limits of agreement (95% CI LOA) was used to assess accuracy. Overall, the DEEP calibration decreased 95% CI LOA compared with the MAT approach for both designs. The Diaphragm design outperformed the Tube design in measuring the primary load vector (joint compression). Importantly, the Diaphragm design permits the hermetic encapsulation of all electronics, which is not possible with the Tube design, given the small size of the trapezium. Substantial work remains before this device can be approved for implantation, but this work lays the foundation for further device development that will be required.

Isolated Osseous Excision in the Adult Carpus: A Narrative Review.

Various pathologies of the adult carpus result in clinical scenarios where excision can be considered and even recommended. In the appropriate patient population, isolated carpal excision can alleviate pain and improve mobility. Excisions of the pisiform, trapezium, and trapezoid have abundant literature evidence to support positive long-term functional outcomes. In contrast, isolated excision of the capitate, hamate, and triquetrum has limited support in the literature secondary to compromise of carpal mechanics and lead to recurrent pain. Additionally, isolated scaphoid and lunate excision are best avoided secondary to carpal collapse and should be paired with concomitant stabilizing procedures in the carpus. This article provides a comprehensive literature review of isolated excision of each osseous carpal bone, their indications, and previously assessed outcomes.