Traumatic thumb carpometacarpal joint dislocations

Trapeziometacarpal joint imaging: Normal high-resolution MRI, US and CT compared with cadaveric specimens and pathological imaging findings

INTRODUCTION

The trapeziometacarpal (TMC) joint is a complex joint, whose anatomy and function are different from the metacarpophalangeal joints of the long fingers. The stability of this joint is ensured at three levels by multiple structures: osteochondral, capsulo-ligamentous, and musculo-tendinous. The anatomical and biomechanical structures ensuring the stability of the TMC joint are perfectly evaluated on magnetic resonance imaging (MRI), with a high degree of confidence. All described ligaments are anatomically visible and perfectly assessed on MRI and ultrasound (US): the dorsoradial ligament, the posterior oblique ligament, the intermetacarpal ligament, the ulnar collateral ligament, the two bundles of the anterior oblique ligament (break ligament), as well as the superficial anterior oblique and deep anterior oblique ligaments.

METHODOLOGY

This educational review assesses the TMC joint anatomy using high-field MRI and US compared with cadaveric specimens as well the biomechanics of this joint. In addition, it highlights pathological patterns of traumatic (sprain, dislocation, and fractures) and degenerative diseases.

RESULTS AND CONCLUSION

Knowledge of TMC joint anatomy is crucial to the radiologists' understanding and assessment of various traumatic and degenerative pathologies, and thus helps clinicians and surgeons choose the appropriate treatment.

Anatomic and Biomechanical Study of Thumb Carpometacarpal Dislocations: A Laboratory Study

BACKGROUND

No previous study recreating an isolated thumb carpometacarpal (CMC) dislocation with or without suture augmentation has been performed in the laboratory. This investigation aimed to evaluate the mechanism and ligamentous complex of isolated thumb CMC dislocations.

METHODS

Biomechanical analysis was performed in 10 cadaveric specimens. A posteriorly directed force or axial loading with hyperflexion through the CMC joint was applied. Load was applied at a rate of 1 mm/s until posterior CMC dislocation was achieved. Maximum load, displacement under nominal loading, stiffness, and mode of failure were recorded. The native ligament was repaired, augmented with high-tensile suture, and testing was repeated.

RESULTS

Posteriorly directed force produced posterior CMC dislocations, while axial loading and hyperflexion through the CMC joint caused fractures. Load-to-failure of the native CMC joint was 217.76 N (SD = 66.03). Stiffness of the ligamentous complex on average was 18.86 N/mm (SD = 8.83). Mean load-to-failure after repair with suture augmentation was 94.62 N (SD = 39.77), with average stiffness of 8.21 N/mm (SD = 3.06). The native ligament was noted to have greater stiffness (P = .002) and greater load-to-failure (P = .0001) than repair with suture augmentation. Maximum displacement-to-failure of the native ligament was 14.5 mm compared with repair with suture augmentation 11.9 mm (P = .068).

CONCLUSION

Isolated CMC dislocation was achieved with a posteriorly directed force rather than hyperflexion of the joint. Ultimate failure load of the repaired ligaments with suture augmentation was about half of that of the native ligaments. Further research into this technique is warranted.

Internal brace augmentation improves the biomechanical properties of trapeziometacarpal joint dorsoradial ligament repair

This study investigated whether dorsoradial ligament repair with internal brace augmentation provided more immediate stability in the trapeziometacarpal joint than dorsoradial ligament repair alone. Seven matched pairs of cadaveric hands were used. One specimen from each pair was assigned to the repair-only group and the other to the repair + internal brace augmentation group. Trapeziometacarpal joint range of motion and translation were quantified under different conditions for both groups: (1) intact, (2) transected dorsoradial ligament, and (3) repaired dorsoradial ligament or repaired dorsoradial ligament plus internal brace augmentation. Load-to-failure tests were performed after repair. Range of motion and translation were increased by dorsoradial ligament transection and were decreased by dorsoradial ligament repair; however, compared to the intact condition, the repair-only group demonstrated greater flexion/extension range, while the repair + internal brace group showed no significant difference in range of motion. Mean loads at 2- and 3-mm displacements were greater in the repair + internal brace group than in the repair-only group (18.0 ± 1.8 N vs. 10.8 ± 1.3 N for 2 mm displacement and 35.3 ± 3.7 N vs. 23.1 ± 2.9 N for 3 mm displacement, respectively). Internal brace augmentation improved the load-to-failure characteristics of dorsoradial ligament repair without compromising range of motion. LEVEL OF EVIDENCE: IV.

Chronic Dislocation of the Thumb Carpometacarpal Joint: A Case Report

Dislocation of the thumb carpometacarpal (CMC) joint is a rare injury; chronic CMC dislocation can lead to significant disability. Traditionally, surgical intervention has focused on the reconstruction of the anterior oblique ligament, though more recently there has been more focus on the dorsoradial ligament. Consideration of both ligaments during CMC joint reconstruction is important to optimize functional outcomes. A 59-year-old male presented with a subacute/chronically dislocated CMC joint of the thumb. Open reduction with pin fixation and dorsoradial ligament repair and augmentation was chosen to restore the stability of the joint. Joint reduction without subluxation was successfully maintained. By 12 weeks postoperatively, there were no remaining major restrictions to activity. Repair of the dorsoradial ligament with augmentation and pinning is a viable approach for surgical management of subacute/chronic dislocation of the thumb CMC joint.

Outcomes of Percutaneous Pinning for Interfragmentary Fixation in Treating Bennett Fractures With Tiny Avulsion Fragments

For Bennett fractures with tiny avulsion fragments, healing may be jeopardized owing to limited fracture contact surface if displacement of reduced fracture junctions occurs. This study aimed to assess the efficacy of treating Bennett fractures with tiny avulsion fragments using percutaneous small-diameter K-wires for tiny fragment fixation and thumb carpometacarpal (CMC) joint transfixation. From 2011 to 2019, we retrospectively enrolled patients with Gedda type 3 Bennett fractures who underwent operation with K-wire percutaneous pinning for the tiny fragment and CMC joint. We enrolled a total of 13 patients (13 fractures) with a mean age of 26.9 years (range, 18-42 years) at operation and a mean follow-up time of 17.9 months (range, 12-34 months). At the final follow-up, the shortened Disabilities of the Arm, Shoulder and Hand Questionnaire mean score was 4.7, and the visual analog scale score for pain during activity was 0.7. Mean grip strength was 34.7 kg (97.7% of the value on the unaffected side). Mean pinch strength was 5.4 kg (90.5% of the value on the unaffected side). Mean first web opening angle was 66.2° (96.6% of the value on the unaffected side). There were no changes in gap and step-off during the healing process and no osteoarthritic changes in the thumb CMC joint at the final follow-up. For Bennett fractures with tiny avulsion fragment, percutaneous treatment with small-diameter K-wires for fragment fixation and thumb CMC joint transfixation provides a viable alternative with fracture healing and good functional outcomes. [Orthopedics. 2023;46(2):103-107.].

Isolated Trapeziometacarpal Joint Dislocation With Five Years of Follow-up: A Case Report and Review of the Literature

Isolated trapezio-metacarpal joint dislocation is a rare injury. Despite being simple to reduce, there is not yet a consensus regarding how to secure the reduction, the type of immobilization, and the postoperative protocol. Herein, we present a rare case of pure trapezio-metacarpal joint dislocation without any associated fractures that was treated with closed reduction and intermetacarpal fixation, six weeks of immobilization, and an early rehabilitation protocol.

Association of Acute Trapeziometacarpal Joint Dislocation and Trapezium Fracture in a 14-Year-Old Boy: A Case Report

Fracture-dislocation of the trapeziometacarpal (TM) joint in adolescent patients is a rare injury, with only 3 cases reported in literature to our knowledge. Its low incidence, together with the complexity of the anatomy and biomechanics of TM joint, may represent a challenge for surgeons in choosing the best treating option. Here, we report a case of a TM fracture dislocation in a 14-year-old boy treated with percutaneous Kirschner wire pinning. The results we obtained endorsed our choice in patients for whom closed reduction is achievable.

Systematic Review of Ligament Reconstruction of Traumatic Isolated Thumb Carpometacarpal Joint Dislocation

INTRODUCTION

Thumb carpometacarpal (CMC) joint dislocations are rare with minimal agreement on surgical management. The dorsoradial ligament (DRL) is the primary joint stabilizer but has not historically been reconstructed. We hypothesize that the reported reconstruction of first CMC joint dislocations primarily uses the flexor carpi radialis (FCR) without collective agreement on a surgical technique.

METHODS

A systematic review of the PubMed database from 1996 to 2022 was done. Keywords were "thumb dislocation," "thumb carpometacarpal dislocation," and "carpometacarpal joint ligament repair." Inclusion criteria included isolated, unstable thumb CMC dislocations with reconstruction. The Preferred Reporting Items for Systematic Reviews and Meta Analyses guidelines were used.

RESULTS

Four hundred thirty-seven records were identified, and nine met inclusion criteria. Two articles were cohort studies, and seven were case reports. Thirty-seven patients were included, and 26 patients had reconstruction with tendonous autograft. Twenty-five (96.2%) used the FCR and 1 (3.9%) from the palmaris longus. Three patients had reconstruction with a suture anchor. Surgical techniques varied between studies.

DISCUSSION

The recommendation of the authors recreates the DRL during autograft repair. Current repair techniques that recreate the DRL use the FCR, but quantitative comparisons of tendonous autografts or suture anchors have not been done.

Thumb Carpometacarpal Instability

The basal joint complex of the thumb provides the framework necessary for function of the human hand. Although its unique saddle articulation allows for a wide range of motion necessary for routine function of the hand, it is rendered inherently unstable because of poor bony congruency and reliance on its capsuloligamentous support. Painful instability of this joint can stem from several causes including traumatic dislocation, various hypermobility conditions, and chronic overuse and microtrauma. A thorough history and examination as well adequate imaging is necessary for proper evaluation of instability. Treatment options range from nonoperative modalities to surgery, which entails closed, percutaneous, or open reduction with numerous ligament repair and reconstruction techniques. Arthroscopy can also serve to be a useful adjunct for assessment of the joint and stabilization of the critical capsuloligamentous structures. This review outlines the critical osseous and soft-tissue anatomy surrounding the thumb carpometacarpal joint, the key points in evaluating patients presenting with acute traumatic and chronic thumb carpometacarpal instability without fracture or arthritis, and reviews both nonoperative and operative treatments of this injury.

Traumatic Isolated Thumb Carpometacarpal Joint Dislocation - Report of Two Clinical Cases

Isolated thumb carpometacarpal joint dislocation is a rare lesion that accounts for less than 1% of all hand lesions.

The authors present two cases of traumatic isolated thumb carpometacarpal joint dislocation. One of them was treated with closed reduction and cast immobilization, and the other was treated with closed reduction, Kirschner-wires pinning, and cast immobilization.

The first patient had a good functional outcome and showed no signs of thumb carpometacarpal instability. The patient treated with Kirschner wires presented signs of clinical instability and radiological subluxation.

Isolated thumb carpometacarpal dislocation is a rare lesion that can cause joint instability, which interferes with the normal function of the hand and can lead to articular degenerative changes.

The best management of this lesion is still controversial, since there is lack of evidence in the literature showing superiority of one treatment over the other.

Management of thumb carpometacarpal joint dislocations: A systematic review

Although rare, thumb Carpometacarpal (CMC) joint dislocations can have significant complications which impact hand function. Optimal management is crucial in restoring pinch and grasp strength, but no agreement exists regarding treatment due to a paucity of literature on this subject. Systematic review was conducted involving non-operative and operative management of the CMC joint. 15 articles with a total of 60 thumbs were evaluated from published literature. 12/60 thumbs with isolated CMC joint dislocations were treated with closed reduction, with 4 cases needing additional ligament repair due to joint instability post-reduction. 51/60 of the isolated CMC joint dislocations had ligament reconstruction, with flexor carpi radialis tendon autograft (29/51) as the most popular option. 60/60 patients regained full function and stability of the CMC joint with significant pain relief. Although good surgical outcomes have been achieved, long term clinical outcome reporting is needed to develop a standardized approach to treatment.

Ligament Reconstruction of Traumatic Pure Dislocation of Carpometacarpal Joint of the Thumb: A Series of Acute and Chronic Cases

Background  Traumatic instability of carpometacarpal (CMC) joint of the thumb without a fracture (pure dislocation of CMC joint) is an uncommon injury, and a universally accepted protocol has not yet been developed for its management. Here, we aim to evaluate the outcome of this injury managed with ligament reconstruction technique, in a series of acute and chronic injuries. Patients and Methods  Total nine patients (six acute and three chronic) with pure dislocation of CMC joint who underwent ligament reconstruction surgery were included in this retrospective study. Outcome measures included disabilities of the arm, shoulder, and hand (quick-DASH) questionnaire; visual analog scale (VAS) scoring system; patient-rated wrist/hand evaluation (PRWHE) system; pinch and grip strength; and Kapandji thumb opposition scores. Results  The patients' mean age was 32.55 ± 11.4 years. Their mean follow-up period was 27 ± 12.8 months. The mean postoperative pinch and grip strength was equivalent to 91.5% and 108% of the contralateral hand, respectively. The mean Quick-DASH score was 14.7 ± 19.4. The mean PRWHE score was 18.7 ± 22.4. The mean VAS was 1.1 ± 1.5. The mean Kapandji score was 8.3 ± 1.4. The pinch and grip strength were considerably superior in acute injuries. Degenerative changes were seen in all joints at the latest follow-up. None of our patients needed a revision surgery. Conclusion  Ligament reconstruction method could result in favorable outcome in the management of pure dislocation of CMC joint. However, delayed surgery of this injury might adversely affect the outcome measures.

Traumatic Dorsoradial Trapezium-Metacarpal Joint Dislocation

A trapezium-metacarpal joint dislocation is a rare pathology reported in <1% of all hand injuries. Due to the rarity of this type of injury, no clear standard of treatment exists. Various treatment approaches are reported in the relevant literature, mainly consisting of anterior and posterior dislocation of the trapezium-metacarpal joint. In this case, a 38-year-old patient was treated for dorsoradial trapezium-metacarpal joint dislocation through open reduction with ligamentous reconstruction. Gradual improvement of the patient’s thumb mobility was observed following several physiotherapy sessions.

Isolated first carpometacarpal joint dislocation managed with closed reduction and splinting

A 56-year-old man, right-hand-dominant office worker, complained of pain and swelling at the base of his right thumb after using his hand to press onto the front passenger seat during an emergency brake. X-ray showed a dorsal dislocation of the first carpometacarpal joint of his right hand. Closed reduction of the joint was performed. As there were no clinical signs of instability post-reduction and X-ray confirmed that the joint was congruent, the joint was immobilised in a thumb spica splint for 6 weeks. His pain subsided and the range of motion of his first carpometacarpal joint was full at 9 weeks post-injury. Two years after the injury, he was asymptomatic and X-ray revealed normal joint anatomy with no obvious subluxation or osteoarthritic change. For patients with first carpometacarpal joint dislocations, non-operative management with splinting is a good option if the joint is stable post-reduction.

A rare case of floating fifth metacarpal and review of literature

Background

Floating metacarpal is a rare concurrent bipolar dislocation of metacarpal at both ends. Isolated dislocations of Carpo-metacarpal (CMC) or Metacarpo-phalangeal (MCP) have been previously reported, simultaneous dislocations of both joints is scarcely reported in literature and bares high chance of diagnosis being missed on presentation.

Patient

A 29-year-old male presented with pain, swelling in left hand and loss of movement in fifth and fourth finger following a motorcycle fall injury. Radiography showed floating metacarpal of fifth ray along with fracture dislocation of at base of fourth metacarpal.

Diagnosis

The patient was diagnosed with floating fifth metacarpal along with fracture dislocation at base of fourth metacarpal.

Intervention

Open reduction and K-wire fixation was performed across CMC for fifth and fourth metacarpal along with MCP fixation for fifth metacarpal joint.

Outcomes

The patient had excellent outcome after one year with normal Range of motion and grip.

Lessons

Early recognition and prompt management of these injuries are considered as hallmark of prognosis. Ideal treatment for such dislocation is controversial. However, we have noted from earlier case reports that with acute dislocation and minimal swelling closed reduction and cast immobilization could be sufficient. In case of delayed presentation or swelling along with fracture, open reduction is favorable choice of treatment.

Chronic Carpometacarpal Dislocation of the Thumb: A Case Report and Review of the Literature

CASE

We report a case of a chronic, irreducible carpometacarpal (CMC) dislocation of the thumb, which was managed with a trapeziometacarpal arthrodesis.

CONCLUSION

This case demonstrates that arthrodesis is a suitable salvage procedure for chronic, irreducible CMC dislocations of the thumb.

Trapezium Fracture Associated with Thumb Carpometacarpal Joint Dislocation: A Report of Three Cases and Literature Review

Isolated trapezium fracture in combination with thumb carpometacarpal (CMC) joint dislocation is extremely rare, and no treatment consensus exists. Herein, we report 3 successfully treated cases of isolated trapezium fracture with thumb CMC joint dislocation. While good short-term results have been reported in the literature, the possibility of substantial ligament injuries that can lead to future instability of the thumb CMC joint must be noted. In order to obtain an excellent long-term clinical result, we propose the consideration of the anatomical repair of the CMC joint in terms of both bony and ligamentous structures in cases where instability remains after fracture fixation.

Assessment of normal trapeziometacarpal joint alignment

The purpose of this study was to determine the alignment of the normal trapeziometacarpal joint and any changes in its alignment with age. Radial, dorsal and dorsoradial subluxation were measured on computerized tomographic scans in 50 joints of 50 adults aged 18 to 62. There were statistically significant correlations between increasing age and dorsoradial subluxation but no significant correlation with dorsal and radial subluxation. Significant dorsoradial subluxation occurs after 46 years of age in the normal trapeziometacarpal joint. A mean dorsoradial subluxation of 21% (range 14%-30%) can be considered normal in this age group.

[Biomechanical evaluation of the first carpometacarpal joint stability by using different reconstruction methods]

Objective

To study the biomechanical differences of the first carpometacarpal joint stability by using different reconstruction methods so as to provide theoretical basis for the clinical choice of reconstruction method.

Methods

The upper limb specimens were selected from 12 fresh adult cadavers, which had no fracture, bone disease, dislocation of wrist joint, deformity, degeneration, or ligament injury on the anteroposterior and lateral X-ray films. The specimens were randomly divided into 5 groups: normal group, injury group, palmar carpometacarpal ligaments reconstruction group, dorsal carpometacarpal ligaments reconstruction group, and palmar and dorsal carpometacarpal ligaments reconstruction group. Three normal specimens were used as normal group, and then were made of the first carpometacarpal joint dislocation models (injury group); after the first carpometacarpal joint dislocation was established in the other 9 specimens; the volar ligament, dorsal ligament, and volar-dorsal ligaments were reconstructed with Eaton-Little method, Yin Weitian method, and the above two methods in 3 construction groups. The biomechanical test was done to obtain the load-displacement curve and to calculate the elastic modulus.

Results

During biomechanical test, ligament rupture and loosening of Kirschner wire occurred in 1 case of injury group and palmar carpometacarpal ligaments reconstruction group; no slipping was observed. The elastic modulus values were (11.61±0.20), (5.39±0.12), (6.33±0.10), (7.12±0.08), and (8.30±0.10) MPa in normal group, injury group, palmar carpometacarpal ligaments reconstruction group, dorsal carpometacarpal ligaments reconstruction group, and palmar and dorsal carpometacarpal ligaments reconstruction group respectively, showing significant differences among groups ( P<0.05).

Conclusion

Volar ligament reconstruction, dorsal ligament reconstruction, and volar-dorsal ligament reconstruction all can greatly improve the stability of the first carpometacarpal joint. And the effect of volar-dorsal ligament reconstruction is the best, but the stability can not restore to normal.

Thumb Injuries in Athletes

Thumb injuries are common in athletes and present a challenging opportunity for upper extremity physicians. Common injuries include metacarpal base fractures (Bennett and Rolando types), ulnar and radial collateral ligament injuries, dislocation of the carpometacarpal and metacarpophalangeal joints, and phalanx fractures. This review, although not exhaustive, highlights some of the most common thumb injuries in athletes. The treating physician must balance pressure from athletes, parents, coaches, and executives to expedite return to play with the long-term well-being of the athlete. Operative treatment may expedite return to play; however, one must carefully weigh the added risks involved with surgical intervention.

Trapeziometacarpal joint dislocation complicated by a trapezium fracture: A case report and literature review

The authors report and discuss the management of a 25-year-old male patient with a trapeziometacarpal joint dislocation complicated by a trapezium fracture. This injury combination is rare with only reported 15 cases. After closed reduction resulted in dorsal instability, anatomical reduction of the trapezium fracture and internal screw fixation were performed using an open approach. This fixation stabilized the joint but was fragile due to the small fragment size. For this reason, ligament reconstruction using half of the flexor carpi radialis tendon was added. At the last follow-up, 16 months later, the trapeziometacarpal joint was stable with a normal range of motion, but the patient had slight pain during physical effort and decreased pinch strength.

Delayed Presentation of Metacarpophalangeal Joint Dislocation of the Thumb in Children Requiring Open Reduction: Two Cases Reported and Review ofLiterature

Introduction:

Dislocation of the metacarpophalangeal joint (MCPJ) of the thumb is rare in children and delayed presentation of this injury is even more uncommon in the literature. We report two cases, both children, who presented to fracture clinic with a dislocated thumb over one week after initial injury. In each case closed reduction was attempted but failed, and open reduction was necessary.

Case Report:

Case Presentation 1: A 4 year-old right-hand dominant girl sustained a hyper-extension injury to her right thumb while on holiday abroad. She was told she has “sprained” her thumb. On review in fracture clinic 10 days later, the MCPJ of her thumb remained swollen and bruised. Radiographs showed a dorsally dislocated MCPJ of the right thumb. Case Presentation 2: A four-year old right-hand dominant boy presented to fracture clinic after being referred from A&E with a left ‘thumb injury’ – his thumb had accidentally been jammed in a door 1 week previously. Radiographs were reviewed and repeated, confirming a MCPJ dislocation.

Conclusion:

Dislocation of the MCPJ of the thumb is extremely uncommon in children and therefore the diagnosis can be easily missed. Two unusual cases of dislocated MCPJ of the thumb in children that presented late because both radiological and clinical features had been missed are described. Closed reduction should always be attempted first but it should be recognised that conversion to an open reduction may be needed, particularly if there is a delay in presentation. There are various surgical options for open reduction including volar and dorsal approaches and arthroscopic procedures. The optimal method is controversial. We have explained a successful open reduction using a dorsal approach. In both cases the volar plate was found to be interposed within the joint blocking reduction. At follow up the patients had regained a full range of movement, normal power and grip strength.

Ligamentous Reconstruction of Traumatic Dislocation of Thumb Carpometacarpal Joint: Case Report and Review of Literature

Introduction:

Thumb carpometacarpal dislocation is a rare injury with many treatment options described in literature.

Case Description:

A 47-year-old male patient presented to hospital with an isolated dorsal dislocation of the thumb carpometacarpal joint. Closed reduction of the dislocation could be easily done but joint was grossly unstable and redislocated. Repair of ruptured dorsoradial ligament and joint capsule was done with immobilization for 6 weeks. At 2-years follow-up evaluation, the patient was pain free and returned to his previous level of activity. No restriction of carpometacarpal movements or residual instability was noticed. Radiographic examination showed normal joint congruity and no signs of osteoarthritis.

Conclusion:

Capsuloligamentous repair can be considered the treatment of choice in thumb carpometacarpal dislocations with instability after closed reduction.

An alternative technique for stabilisation of the carpometacarpal joint of the thumb after dislocation or subluxation

We report a new surgical technique for the treatment of traumatic dislocation of the carpometacarpal (CMC) joint of the thumb. This is a tenodesis which uses part of the flexor carpi radialis.

Between January 2010 and August 2013, 13 patients with traumatic instability of the CMC joint of the thumb were treated using this technique. The mean time interval between injury and ligament reconstruction was 13 days (0 to 42). The mean age of the patients at surgery was 38 years: all were male.

At a mean final follow-up of 26 months (24 to 29), no patient experienced any residual instability. The mean total palmar abduction of the CMC joint of the thumb was 61° and the mean radial abduction 65° The mean measurements for the uninjured hand were 66° (60° to 73°) and 68° (60° to 75°), respectively. The mean Kapandji thumb opposition score was 8.5° (8° to 9°). The mean pinch and grip strengths of the hand were 6.7 kg (3.4 to 8.2) and 40 kg (25 to 49), respectively. The mean Disabilities of the Arm, Shoulder, and Hand questionnaire score was 3 (1 to 6). Based on the Smith and Cooney score, we obtained a mean score of 85 (75 to 95), which included four excellent, seven good, and two fair results.

Our technique offers an alternative method of treating traumatic dislocation of the CMC joint of the thumb: it produces a stable joint and acceptable hand function.

Cite this article: Bone Joint J 2015;97-B:1533–8.

Altered Innervation Pattern in Ligaments of Patients with Basal Thumb Arthritis

Purpose The population of mechanoreceptors in patients with osteoarthritis (OA) lacks detailed characterization. In this study, we examined the distribution and type of mechanoreceptors of two principal ligaments in surgical subjects with OA of the first carpometacarpal joint (CMC1). Methods We harvested two ligaments from the CMC1 of eleven subjects undergoing complete trapeziectomy and suspension arthroplasty: the anterior oblique (AOL) and dorsal radial ligament (DRL). Ligaments were divided into proximal and distal portions, paraffin-sectioned, and analyzed using immunoflourescent triple staining microscopy. We performed statistical analyses using the Wilcoxon Rank Sum test and ANOVA with post-hoc Bonferroni and Tamhane adjustments. Results The most prevalent nerve endings in the AOL and DRL of subjects with OA were unclassifiable mechanoreceptors, which do not currently fit into a defined morphological scheme. These were found in 11/11 (100%) DRLs and 7/11 (63.6%) AOLs. No significant difference existed with respect to location within the ligament (proximal versus distal) of mechanoreceptors in OA subjects. Conclusion The distribution and type of mechanoreceptors in cadavers with no to mild OA differ from those in surgical patients with OA. Where Ruffini endings predominate in cadavers with no to mild OA, unclassifiable corpuscles predominate in surgical patients with OA. These findings suggest an alteration of the mechanoreceptor population and distribution that accompanies the development of OA. Clinical Relevance Identification of a unique type and distribution of mechanoreceptors in the CMC1 of symptomatic subjects provides preliminary evidence of altered proprioception in OA.

Primary repair of capsuloligamentous structures of trapeziometacarpal joint: A preliminary study

BACKGROUND

Isolated trapezio-metacarpal joint dislocation is uncommon and challenging since controversy still exists regarding its management.

DESCRIPTION

We present a short case series in which direct repair of trapezio-metacarpal ligaments was done in three patients who had isolated, unstable dislocation of the thumb carpometacarpal joint. All of them were engaged in tasks where no compromise in hand functions and grip strength was affordable. The dislocation was addressed primarily by repair of volar oblique and dorsoradial ligaments with suture anchors. The joint was immobilised in a cast for 4 weeks followed by gradual mobilisation.

RESULTS

At an average follow up of 15 months, all the three patients have no restriction in the range of motion. There are no symptoms and signs of instability. In two patients, there is no pain at all; while one patient has occasional pain which is mild and does not interfere with the hand function. Radiographic examination showed normal joint alignment and no signs of subluxation or early osteoarthritis.

CONCLUSION

Repair of the capsuloligamentous complex with suture anchors may be considered as a treatment option in unstable trapezio-metacarpal joint dislocations in high demand patients.

Ultrastructure and innervation of thumb carpometacarpal ligaments in surgical patients with osteoarthritis

BACKGROUND

The complex configuration of the thumb carpometacarpal (CMC-1) joint relies on musculotendinous and ligamentous support for precise circumduction. Ligament innervation contributes to joint stability and proprioception. Evidence suggests abnormal ligament innervation is associated with osteoarthritis (OA) in large joints; however, little is known about CMC-1 ligament innervation characteristics in patients with OA. We studied the dorsal radial ligament (DRL) and the anterior oblique ligament (AOL), ligaments with a reported divergent presence of mechanoreceptors in nonosteoarthritic joints.

QUESTIONS/PURPOSES

This study's purposes were (1) to examine the ultrastructural architecture of CMC-1 ligaments in surgical patients with OA; (2) to describe innervation, specifically looking at mechanoreceptors, of these ligaments using immunohistochemical techniques and compare the AOL and DRL in terms of innervation; and (3) to determine whether there is a correlation between age and mechanoreceptor density.

METHODS

The AOL and DRL were harvested from 11 patients with OA during trapeziectomy (10 women, one man; mean age, 67 years). The 22 ligaments were sectioned in paraffin and analyzed using immunoflourescent triple staining microscopy.

RESULTS

In contrast to the organized collagen bundles of the DRL, the AOL appeared to be composed of disorganized connective tissue with few collagen fibers and little innervation. Mechanoreceptors were identified in CMC-1 ligaments of all patients with OA. The DRL was significantly more innervated than the AOL. There was no significant correlation between innervation of the DRL and AOL and patient age.

CONCLUSIONS

The dense collagen structure and rich innervation of the DRL in patients with OA suggest that the DRL has an important proprioceptive and stabilizing role.

CLINICAL RELEVANCE

Ligament innervation may correlate with proprioceptive and neuromuscular changes in OA pathophysiology and consequently support further investigation of innervation in disease prevention and treatment strategies.

Carpometacarpal dislocation of the thumb associated with fracture of the trapezium

Carpometacarpal dislocation (CMC) of the thumb associated with fracture of trapezium is an extremely rare injury, with only 12 cases that sustained similar injuries reported in the literature. In this article, another patient with this rare injury was reported, and all previously published cases were extensively reviewed. The presented case and all previously published cases had a longitudinally oriented trapezium fracture, which is naturally unstable and almost always associated with dislocation of the CMC joint. In contrast to previous descriptions, we believe that CMC joint dislocation and trapezium fracture are not two distinct pathologies that occur simultaneously by chance but share cause and consequence.

Intra-articular fractures of the hand

Fractures of the hand are common injuries and in particular, fractures involving the articular surfaces can present difficulties to the orthopedic surgeon in practice. Although the treatment of these fractures needs to be individualized based on fracture pattern and location, the goals for these fractures are to restore the alignment, stability, and congruity and to allow for early motion to prevent stiffness and traumatic arthritis. This article classifies the various types of intra-articular hand fractures as well as the workup and management of these injuries.

The carpometacarpal joint of the thumb: MR appearance in asymptomatic volunteers

PURPOSE

To prospectively characterize the MR appearance of the carpometacarpal (CMC) joint of the thumb in asymptomatic volunteers.

MATERIALS AND METHODS

Thirty-four asymptomatic volunteers (17 women, 17 men, mean age, 33.9 ± 9.2 years) underwent MR imaging of the thumb after approval by the local ethical committee. Two musculoskeletal radiologists independently classified visibility and signal intensity (SI) characteristics of the anterior oblique (AOL/beak ligament), the posterior oblique (POL), the intermetacarpal (IML), and the dorsoradial ligaments (DRL) on a three-point Likert scale. The thickness of all ligaments, cartilage integrity, and presence of joint fluid were assessed. The alignment of the first metacarpal base with the trapezium was quantified on sagittal and coronal planes.

RESULTS

The ligaments of the CMC joint were constantly visible in all volunteers for the POL and IML, and in all but one for the AOL and DRL. On intermediate-weighted fat-saturated images the POL (65 %/74 % reader 1/reader 2) and DRL (58 %/64 %) were commonly of increased SI, while the IML had a striated appearance in 91 %/76 % of subjects. The AOL showed a variable SI (36 %/42 % low, 27 %/27 % increased, 36 %/30 % striated). The IML was the thickest ligament with a mean of 2.9 mm/3.1 mm and the DRL the thinnest (1.2 mm/1.4 mm). There was a mean dorsal subluxation of 1.8 mm/2.0 mm and radial subluxation of 2.8 mm/3.4 mm of the metacarpal base. The AOL was significantly thicker in men (1.7 mm) than in women (1.2 mm; p = 0.02). Radial subluxation was significantly larger in men (3.4 mm) than in women (2.2 mm; p = 0.02). No subluxation in palmar or ulnar direction was seen.

CONCLUSIONS

Radial and dorsal subluxation of the CMC joint can be a normal finding in a resting position at MR imaging. The CMC ligaments showed a considerable variability of signal intensity with a typically striated IML; thickness of the AOL is typically less than 2.2 mm, of the POL typically less than 2.9 mm.

A painful thumb

Isolated traumatic carpometacarpal (CMC) dislocation of the thumb is a rare injury. There are many different ways to manage a thumb CMC joint dislocation which ranges from closed reduction with or without Kirschner wires and casting to ligament reconstruction. However, it is still up for debate on the best management for this injury. We describe a case of isolated traumatic carpometacarpal dislocation of the first CMC joint in a 22-year-old student and reviewed the evidence on management. Our patient was managed with manipulation under anaesthesia (MUA). She returned to preinjury activities with no difficulties within 2 months. Good outcomes can be achieved with MUA to manage dislocation of the first CMC joint; however, those with high activity of the hand may also benefit from ligament reconstruction.

Bilateral carpometacarpal joint dislocations of the thumb

A traumatic carpometacarpal joint dislocation of the thumb accounts for less than 1% of all hand injuries. Optimal treatment strategies for this injury are still a subject of debate. In this article, we report a case of bilateral thumb carpometacarpal joint dislocations: a unique combination of injuries. We believe our case is the second report of bilateral carpometacarpal joint dislocation regarding the thumb in English literature. It was successfully treated with closed reduction and percutaneous K-wires fixation on one side, and an open reduction and reconstruction of the ligament on the other side.

Modified Eaton-Littler's Reconstruction for Traumatic Dislocation of the Carpometacarpal Joint of the Thumb-A Case Report and Review of Literature

Isolated traumatic dislocation of the carpometacarpal joint of the thumb is an uncommon injury. Left untreated, resulting mechanical instability of this joint interferes with normal function of the hand and can lead to articular degeneration of the joint. Most are amenable to closed reduction with or without supplementary pinning. We present a case of a 21 year old female patient with continual instability of the carpometacarpal joint of her right thumb, following closed reduction and pinning. Surgical stabilization was achieved by anterior oblique ligament reconstruction using a Modified Eaton- Littler's technique. At 1 year follow-up evaluation the patient was pain free with no clinico-radiological evidence of instability.

Current concepts of the anatomy of the thumb trapeziometacarpal joint

This review article describes the anatomy of the thumb trapeziometacarpal joint. In the final phase of opposition screw home torque rotation of the volar beak of the thumb metacarpal in the pivot area of the trapezium recess and tension on the dorsal ligament complex create stability for power pinch and power grip. The resulting compressive shear forces can lead over time to trapeziometacarpal joint osteoarthritis.

Isolated thumb carpometacarpal joint dislocation: a case report and review of the literature

Background

Isolated thumb carpometacarpal dislocation is a rare injury pattern and the optimal treatment option is still controversial.

Case Description

We present a 27-year-old basketball player who underwent an isolated dorsal dislocation of the thumb carpometacarpal joint after a fall. The dislocation was successfully reduced by closed means but the joint was found to be grossly unstable. Due to inherent instability, repair of the ruptured dorsoradial ligament and joint capsule was performed.

The ligament was detached from its proximal insertion into trapezium and subsequently stabilized via suture anchors. The torn capsule was repaired in an end-to-end fashion and immobilization of the joint was applied for 6 weeks.

Results

At 3-year follow up evaluation the patient was pain free and returned to his previous level of activity. No restriction of carpometacrpal movements or residual instability was noticed. Radiographic examination showed normal joint alignment and no signs of subluxation or early osteoarthritis.

Conclusion

Surgical stabilization of the dorsal capsuloligamentous complex may be considered the selected treatment option in isolated carpometacarpal joint dislocations, that remain unstable after closed reduction in young and high demand patients.

Level of Clinical Evidence: Level IV

Unusual pattern of dislocation of the trapeziometacarpal joint with avulsion fracture of the trapezium: case report

Dislocation of the trapeziometacarpal joint is a rare injury. We report an unusual pattern of dorsal dislocation of the trapeziometacarpal joint with an avulsion fracture of the dorsoradial tubercle of the trapezium. Simultaneous ligament rupture with an avulsion fracture of the thumb metacarpophalangeal joint was associated. The trapeziometacarpal joint was reduced and disrupted ligaments with avulsed fragments of both joints were surgically repaired.