Patient presented with pain and swelling at the volar surface of the right hand.
A 63-year-old man presented with two week history of pain and swelling of the volar surface of the right hand between the third and fourth metacarpal bones. He refers to a hand injury with a palm tree spine (palm thorn) two months ago. The foreign body was not detected in his first visit to a near outpatient clinic, and antibiotic treatment was started. The physical examination reveals tenderness and pain in the palm, with pain related to flexion movements although no limitation for flexion or extension was noted. Ultrasound shows an echogenic lineal foreign body with a posterior acoustic shadowing located between the third and fourth metacarpal bones surrounded by a hypoechoic rim region. Due to the deepness of the foreign body with carpal 3rd and 4th metacarpal shadow the distal portion of the spine could not be accurately seen, therefore a hand MRI was performed. T1 and T2 weighted MR images confirmed the presence of a lineal hypointense foreign body of 21 mm surrounded by fluid collection of 24 x7 mm as well as edema in interosseous muscles. The distal part of the spine and the surrounding collection had contact with the third flexor digitorum superficialis which explained the palmar pain increasing with flexion movement.
Soft tissue foreign bodies are a common clinical problem in both adults and children. The diagnostic approach for this clinical situation can be a challenging process, especially when there is no clear previous trauma history. However the finding of prolonged swelling and inflammation with a poor respond to therapy should alert the physician for the possibility of a soft tissue mass associated with a long standing foreign body. Wood, thorns, spines and other vegetative foreign bodies are considered highly inflammatory. Among these, palm tree spines are known to cause a protracted local reaction due to their composition made of alkaloids. The timing of the injury is important evaluating spines. Older injuries may present with infection, induration or granuloma formation with further complications such as osteomyelitis, arthritis and delayed tendon or nerve injury. Traditionally, plain films have primarily been used in the detection of soft tissue foreign bodies. However, these procedures are only successful if the object is radiopaque and radiation exposure is required. Ultrasonography (US) has a high availability and provides a good alternative to identify non radiopaque superficial foreign bodies, along with evaluation of their associated soft tissue complications without the risk of ionizing radiation. It allows determination of the precise location and aids for further removal. US may be less accurate if the foreign body is located adjacent to bone or deep to subcutaneous gas. False positive findings can potentially result from calcifications, scar tissue, fresh hematoma, or air trapped in the soft tissue. This technique has the limitation to be operator dependence. Computed tomography is not a good imaging method due to the bad differentiation between normal soft tissue structures and inflammatory response, and require radiation. Magnetic resonance (MR) is helpful identifying non-radiopaque objects and has the advantages of multiplanar imaging with excellent delineation of soft tissues which facilitates the visualization of foreign bodies in their entirety along with the associated complications. Moreover foreign bodies located within bones and its relation with deep tendons can also be perfectly assessed as in this case. However, MR sometimes does not allow differentiation of foreign bodies that have low intensity from other structures that have low signal intensity, such as scar tissue, tendons and calcifications. Imaging procedures provide the physician the knowledge of the exact location of foreign bodies, related structures and complications. They are an especially useful tool for surgical planning.
Right hand soft tissue foreign body
Based on the provided MRI images of the right hand, a relatively long, strip-shaped abnormal signal can be observed in the palmar soft tissue. The boundary between this abnormal signal and the surrounding soft tissue remains relatively clear, with varying degrees of soft tissue edema or inflammatory changes visible around it, suggesting chronic inflammation or granulation tissue reaction in the local tissue. On certain sequences (such as T1-weighted or T2-weighted images), the presumed foreign body signal appears as low or mixed signal intensity, taking on a slender, rod-like shape, which is consistent with the common imaging characteristics of vegetative or wooden foreign bodies. No obvious bony destruction is identified, but attention should be paid to the relationship with important structures such as the palmar aponeurosis, deep tendons, and the neurovascular bundle.
Among the above potential diagnoses, “vegetative foreign body retention with chronic inflammation or granulomatous reaction” most closely matches the patient’s current clinical symptoms and imaging findings, and is therefore the primary consideration.
Combining the patient’s past history of trauma or puncture injury (even if not clearly recalled), the current clinical presentation (palmar pain and swelling that has persisted for a long time), and the strip-shaped foreign body shadow noted on MRI, the most likely final diagnosis is:
Retention of a vegetative foreign body (palm spine or similar wooden splinter) in the right palm with chronic inflammatory granulation reaction.
If any clinical doubt remains or more certainty regarding the nature of the foreign body is required, fine-needle aspiration under ultrasound or MRI guidance, or direct surgical exploration and removal of the foreign body for pathological confirmation may be considered.
In order to restore right-hand function as soon as possible and prevent post-operative adhesions and stiffness, a gradual and individualized rehabilitation program is needed. The following exercise prescription may be considered:
Throughout the rehabilitation process, the exercise intensity and content should be adjusted based on changes in hand swelling and pain to avoid secondary injury. If marked swelling, severe pain, or other abnormalities occur, please seek medical attention promptly.
This report is based on the provided case and imaging information for reference only, and cannot replace face-to-face consultation or professional medical advice. If there are any further changes in the condition or questions, please consult a qualified clinical physician and integrate other test results for a comprehensive evaluation.
Right hand soft tissue foreign body
