Traumatic injuries of the hand
The hand is perhaps the organ of our body which allows the greater affirmation of our humanity, becoming a key tool for interacting with the world around us, allowing us to perform different functions necessary for dayly tasks, so the traumatic injuries that affect it have particular importance in our social life, being more serious if they meet the so-called active side, which varies according to the dominant hand is the left or right.
The hand is the segment of the body most affected by traumatic injuries that can be bruises, wounds, burns, crush injurie , amputations or abrasions .
Due to its specificity, exists even a medical sub-specialty common to Plastic Surgery and Orthopedic Surgery, which is the Hand Surgery.
In anatomical terms, starting with the skeletal parts, hand consists of two rows of small bones with a predominately cubic shape, the carpal bones, which engage in five elongated bones, the metacarpals, serving as anchor to two or three more small bones, the phalanges.
The bone structures are joined together by a complex network of ligaments which maintains stability, and this cohesion is enhanced by the joint capsule surrounding the various joints.
On the end of bone structure slides fibrous cords arranged in a beam, corresponding to the tendons controlling the mobility of this important organ of the human body, existing two flexor tendons and one extensor tendon in each finger .
Besides the tendons there are still the intrinsic hand muscles, as well all the structures that allow the vitality and functioning of this anatomic region, including vessels, nerves, skin and subcutaneous tissue .
Following a trauma, all these noble structures may be achieved, resulting in various types of lesions.
In the case of fractures, at the level of the carpal bones must be highlighted the fractured scaphoid, a bone with limited vascularization, a fact that hinders healing specially in its proximal pole, forcing a prolonged immobilization with a plaster cast involving the thumb, or, in certain cases, to surgical treatment.
Fractures of the metacarpals and phalanges may present various patterns and in case that they reach the joint area or have a significant misalignment may require surgical reduction and fixation with steel wires or small plates and screws. They may occur in the head, neck, shaft or its base. Within the fracture of the metacarpal bone there are some deserving special mention, those who reach the base of the first metacarpal known as Roland or Bennett fractures, often requiring surgical treatment and internal fixation. Also very common is the fracture of the base of the fifth metacarpal, usually due to a punch, in which his head drops toward palmar direction and is usually treated conservatively with manipulation, reduction and immobilization. Articular fractures of the phalanges may require surgical treatment .
In the case of dislocations, the most frequent are the interphalangeal dislocations. There is an injury that sometimes goes unnoticed, requiring a high index of suspicion and particular attention, the transescafoperilunar dislocation. Another carpal injury that may occur is the semilunar dislocation. Both of those lesions should be readily reduced.
Ligament injuries are more frequent in the collateral ligaments that attach the interphalangeal and metacarpal-phalangeal joints and may be partial or complete and there is a particular case of the so-called "game keeper thumb", which reaches the base of the thumb and may cause instability requiring surgical treatment .
The lesions affecting tendons usually occur as a result of simple wounds, usually due to glass or sharp metal, or as a result of complex wounds involving the tendons, but also may arise from sudden pulls causing the mallet finger, which comprises the rupture of the extensor at its insertion on the distal phalanx, with or without bone fragment. Treatment is usually conservative using devices suitable for this purpose, but may be surgical if is possible the reintegration of the tendon. Another type of injury is boutonniere finger, in which there is partial rupture of the tendon near the proximal interphalangeal joint, resulting in a characteristic deformity and usually treated with immobilization in extension using dedicated splints.
As we can infer from what was previously stated, the clinical presentation is variable according to the diversity of pathology, but has in common usually joint pain, swelling and functional impotence .
In general, immobilization of the fingers should not be too long because the resultant stiffness and loss of mobility, with often option for early movement, temporally lower than the time to provide full consolidation of the fracture.
When we suspect of bone lesions, the X-Ray is usually enough for diagnosis, the ultrasound may be useful for study of tendon injuries and in cases requiring more definition we can do a scan with CT or MRI .