in the temporal fossa, jaw, face, and upper parts of the neck. Then notice whether the masseter muscle is rigid, or becomes rigid on any attempt to open the mouth, and if there is any spasm or rigidity of the muscles elsewhere, especially in the neck and spine. <Callout type="important" title="Important">If the joint itself is swollen, tender, and a slight movement in it is painful, it is a case of acute arthritis; this often ends in suppuration, and pus is discharged either into the auditory meatus, the mouth, or behind the ramus of the jaw. The disease may lead to necrosis of the condyle of the jaw or to ankylosis of the joint.</Callout> This joint is not infrequently the site of a pysemic arthritis. It is also frequently one of those involved in acute polyarticular osteo-arthritis. If there is a painful, tender swelling near the joint, the cause of the trismus is evident; common examples are afforded by mumps, tonsillitis, temporal abscess, alveolar abscess, acute lymphadenitis. <Callout type="warning" title="Warning">If there is no local swelling, but the muscles closing the jaw are felt to be rigid and are the seat of severe painful spasms, it is a case of tetanus; the extension of the spasm to the muscles of the trunk will confirm the diagnosis.</Callout> (See p. 30.) If there is no local swelling, and the jaws are held closed by rigid muscles, but there are no painful spasms and the muscles of the neck and trunk are not involved, it is a case of reHex trismus. The cause of the trouble will usually be found in a carious tooth or an imperfectly erupted wisdom-tooth. Chronic trismus — The existence of a tumour in the parotid or submaxillary region or in the mouth or pharynx, preventing opening of the jaws, is readily recognized. The finger in the mouth can easily detect firm cicatricial bands causing cicatricial trismus. <Callout type="tip" title="Tip">When the movement of the jaw is attended with pain and a sense of grating in the joint, which in many cases is perceived by the surgeon, and the condyle is felt to be enlarged, there is osteo-arthritis.</Callout> When the movement of the joint is very limited, and there is neither tumour nor fibrous band nor rigid muscle to account for it, there is fibrous ankylosis. <Callout type="risk" title="Risk">When the joint is immovable, and there is no cause for this outside the joint, the condition is one of true or bony ankylosis. A skiagram will show the synostosis.</Callout> A scar may mark the seat of an abscess from suppuration in the joint, or a wound which has caused fracture involving the joint. If this occurs in children it leads to considerable deformity from imperfect development of the bones. The ankylosis may be unilateral or bilateral. Movement of this joint is sometimes attended with a sudden and painful slip or catch, due to a slight displacement of the interarticular fibro-cartilage.
Key Takeaways
- Identify acute arthritis by swelling, tenderness, and pain in the joint.
- Recognize tetanus through rigid jaw muscles and painful spasms.
- Diagnose reHex trismus from carious teeth or wisdom-tooth issues.
Practical Tips
- Check for grating sensations when diagnosing osteo-arthritis to confirm diagnosis.
- Look for firm cicatricial bands in the mouth that could indicate chronic trismus.
- Use a skiagram to identify true bony ankylosis if joint immobility persists.
Warnings & Risks
- Be cautious of tetanus, as it can extend to muscles of the trunk and be life-threatening.
- Avoid misdiagnosing reHex trismus with other conditions like fibrous bands or tumors.
- Do not overlook carious teeth or wisdom-tooth issues in diagnosing reHex trismus.
Modern Application
While this chapter provides valuable insights into diagnosing jaw and temporal fossa diseases, modern medical techniques have advanced significantly. However, the principles of careful observation and accurate diagnosis remain crucial for survival situations where immediate access to specialized equipment may be limited.
Frequently Asked Questions
Q: How can I identify acute arthritis in someone with a painful jaw joint?
Acute arthritis is identified by swelling, tenderness, and pain in the joint. The condyle might also feel enlarged during examination.
Q: What are the signs of tetanus that should be looked for in trismus cases?
Tetanus presents with rigid jaw muscles and painful spasms. If the spasm extends to the muscles of the trunk, it confirms the diagnosis.
Q: How can I differentiate between reHex trismus and other causes of jaw rigidity?
ReHex trismus is typically caused by carious teeth or an imperfectly erupted wisdom-tooth. Look for these specific dental issues as a primary cause.