Magnetic resonance imaging of acute tendon injury in the finger

Sports Injury-Related Fingers and Thumb Deformity Due to Tendon or Ligament Rupture

Background:

Hand injuries are very common in sports, such as skiing and ball sports. One of the major reasons causing hand and finger deformity is due to ligament and tendon injury. The aim of this study was to investigate if the high-resolution 3T magnetic resonance imaging (MRI) can demonstrate the complex anatomy of the fingers and thumb, especially the tendons and ligaments, and provide the accurate diagnosis of clinically important fingers and thumbs deformity due to ligamentous and tendinous injuries during sport activities.

Methods:

Sixteen fresh un-embalmed cadaveric hands were harvested from eight cadavers. A total of 20 healthy volunteers' hands and 44 patients with fingers or thumb deformity due to sports-related injuries were included in this study. All subjects had MR examination with T1-weighted images and proton density-weighted imaging with fat suppression (PD FS) in axial, coronal, and sagittal plane, respectively. Subsequently, all 16 cadaveric hands were sliced into 2-mm thick slab with a band saw (six in coronal plane, six in sagittal plane, and four in axial plane). The correlation of anatomic sections and the MRI characteristics of tendons of fingers and the ulnar collateral ligament (UCL) at the metacarpal phalangeal joint (MCPJ) of thumb between 20 healthy volunteers and 44 patients (confirmed by surgery) were analyzed.

Results:

The normal ligaments and tendons in 16 cadaveric hands and 20 volunteers' hands showed uniform low-signal intensity on all the sequences of the MRI. Among 44 patients with tendinous and ligamentous injuries in the fingers or thumb, 12 cases with UCL injury at MCPJ of the thumb (Stener lesion = 8 and non-Stener lesion = 4), 6 cases with the central slip injury, 12 cases with terminal tendon injury, and 14 cases with flexor digitorum profundus injury. The ligaments and tendons disruption manifested as increased signal intensity and poor definition, discontinuity, and heterogeneous signal intensity of the involved ligaments and tendons.

Conclusions:

Sports injury-related fingers and thumb deformity are relatively common. MRI is an accurate method for evaluation of the anatomy and pathologic conditions of the fingers and thumb. It is a useful tool for accurate diagnosis of the sports-related ligaments and tendons injuries in hand.

Mri ‘Magic Angle’ Imaging of Finger Tendons

The value of using the technique of magic angle MR imaging to demonstrate finger tendons is explored. Images of fresh frozen cadaveric specimens are presented and the structures that can be visualized in the finger are described. The results suggest that magic angle MR imaging may be a useful non-invasive technique of visualizing the details of the tendons and their surrounds in the hand.

[Finger flexor tenolysis]

Flexor tendon adhesions in zone II are common. The origin of these adhesions is multifactorial. Flexor tenolysis consists of releasing the adhesions to restore the tendon's normal path and the patient's active range of motion. This surgery is complex and extremely delicate. It must be associated with early active mobilization. Any surgical procedure that would hamper this active mobilization must be completed before the flexor tenolysis. The patient should be informed of the risk of flexor digitorum profundus rupture, which is the main complication of this surgery.

Closed mallet thumb injury: a review of the literature and case study of the use of magnetic resonance imaging in deciding treatment

SUMMARY

At present, the literature dedicated to closed mallet thumb injury offers conflicting evidence between conservative and operative approaches. Although conservative treatment is often successful, retraction of the extensor pollicis tendon may lead to improper reattachment and continued deformity. This discussion and case report serve to highlight the use of magnetic resonance imaging as an adjunct in selecting the proper treatment strategy for this injury at initial presentation.

The role of ultrasound in the evaluation of sports medicine injuries of the upper extremity

The two major imaging modalities used for assessment of soft tissue injuries are ultrasound and MRI. Although ultrasound of the extremities is used only to a limited extent in the United States, it is widely used in many other countries for evaluation of extremity injuries. This article first considers the advantages and disadvantages of MRI and ultrasound. Understanding these differences will help the reader understand the role of ultrasound as compared with MRI in evaluating upper extremity injuries. The uses of ultrasound for evaluating sports medicine injuries in specific regions of the upper extremity are then reviewed. Where the data are available, the reported accuracy of ultrasound is compared with MRI for each type of injury.

Quantitative evaluation of equine deep digital flexor tendon morphology using magnetic resonance imaging

Injury of the distal aspect of the deep digital flexor tendon (DDFT) is a recognized cause of lameness, but diagnosis is difficult. This study aimed to improve understanding of DDFT morphology and pathology using retrospective evaluation of magnetic resonance (MR) images. We hypothesized that: (1) The distal aspect of the DDFT in normal horses would have a repeatable proximal/distal pattern and symmetry between limbs and between lobes; (2) DDFT dimensions would be related to bodyweight, navicular bone dimensions and hoof size; (3) this symmetry and pattern would be lost in DDFT injury; and (4) DDFT size would increase with injury. MR images of 64 live horse limbs, 26 with no identified DDFT lesion and 38 with identified DDFT abnormalities, and 19 normal cadaver limbs were analyzed. Using standardized transverse images, measurements of DDFT cross-sectional area, medial-lateral (ML) width and dorsal-palmar depth were obtained at six preselected sites. A uniform distal to proximal shape pattern was identified in all horses. The flattened crescent shape at the insertion changed to a deeper bilobed shape more proximally, with the mid-navicular area having the greatest cross-sectional area. Strong ML (P < 0.0006) and left/right symmetry (P < 0.02) were observed. In addition, there was a strong association between DDFT cross-sectional area and horse weight (P = 0.005) and between DDFT and navicular bone ML width (P = 0.004). Symmetry between sides or between lobes was lost at sites with a unilateral lesion and correlation between horse weight and DDFT cross-sectional area was lost in the presence of lesions. DDFTs with core lesions had a consistent increase in cross-sectional area overall, but other lesion types had no significant increase in size. The shape and symmetry seen in normal tendons could be related to the mechanical demands placed upon individual lobes. The limited increase in cross-sectional area with injury may be explained by the restrictive structures of the hoof, possibly explaining the ongoing pain seen in such lesions.

Extensor mechanism of the fingers: MR imaging-anatomic correlation

Extension of the fingers is a complex function carried out by simultaneous action of extrinsic and intrinsic muscles, as well as retinacular structures in the dorsum of the wrist, hand, and fingers that support and coordinate the action of the muscles. The extensor mechanism of the fingers is divided into topographic zones, which extend from the forearm to the distal phalanx. Magnetic resonance (MR) imaging shows in detail the musculotendinous and retinacular structures of the extensor apparatus. In the different extensor zones, MR imaging findings are similar to those seen macroscopically in anatomic sections. Understanding of and familiarity with the extensor anatomy of the hand and fingers by the radiologist is crucial for better assessment of pathologic conditions with MR imaging and optimization of this modality as a diagnostic tool. Extensor tendon injuries and tenosynovitis represent clinical situations in which knowledge of this anatomy is useful for the clinical radiologist.

MR imaging of ligament and tendon injuries of the fingers

Magnetic resonance (MR) imaging can provide important information for diagnosis and evaluation of soft-tissue trauma in the fingers. An optimal imaging technique should include proper positioning, dedicated surface coils, and specific protocols for the suspected abnormalities. Familiarity with the fine anatomy of the normal finger is crucial for identifying pathologic entities. MR imaging is a powerful method for evaluating acute and chronic lesions of the stabilizing articular elements (volar plate and collateral ligaments) of the fingers and thumbs, particularly in the frequently affected proximal interphalangeal and metacarpophalangeal joints. As in other body regions, MR imaging is also useful for depicting traumatic conditions of the extensor and flexor tendons, including injuries to the pulley system. In general, normal ligaments and tendons have low signal intensity on MR images, whereas disruption manifests as increased signal intensity. Radiologists need to understand the full spectrum of finger abnormalities and associated MR imaging findings.

The role of magnetic resonance imaging in late presentation of isolated injuries of the flexor digitorum profundus tendon in the finger

Four patients had magnetic resonance imaging (MRI) after a clinical diagnosis of a flexor digitorum profundus tendon rupture of the hand. The delay before presentation ranged from 1 to 5 weeks. Three patients had closed ruptures and one had a minor laceration which had healed. MRI showed proximal retraction of the profundus tendon to the palm in two patients and limited retraction in the other two. MRI provides important preoperative information for surgical decision-making and planning in patients who present late with closed flexor tendon injuries of the hand.