Rotation results in an obvious misalignment between PII (the short pastern bone) and PIII (the coffin bone). If rotation of the third phalanx continues, its tip can eventually penetrate the sole of the foot. Sinking is less common and much more severe. It results when a significant failure of the interdigitation between the sensitive and insensitive laminae around a significant portion of the hoof occurs. The destruction of the sensitive laminae results in the hoof wall becoming separated from the rest of the hoof, so that it drops within the hoof capsule. Sinking may be symmetrical, i.e., the entire bone moves distally, or asymmetric, where the lateral or medial aspect of the bone displaces distally. Pus may leak out at the white line or at the coronary band. In extreme cases, this event allows the tip to eventually penetrate the sole of the foot. A severe "sinker" usually warrants the gravest prognosis and may, depending upon many factors, including the quality of aftercare, age of the horse, diet and nutrition, skill, and knowledge and ability of the attending veterinarian and farrier(s), lead to euthanasia of the patient. Phases of laminitis
Treatment and prognosis depend on the phase of the disease, with horses treated in earlier stages often having a better prognosis. Developmental phaseThe developmental phase is defined as the time between the initial exposure to the causative agent or incident, until the onset of clinical signs. It generally lasts 24–60 hours, and is the best time to treat a laminitis episode.
It rarely involves the temporomandibular joint (TMJ) and most publications are case reports.Synovial chondromatosis occurs twice as commonly in males as females and usually in their forties. However, online communities for synovial chondromatosis patients have yielded a stark contrast, with equal representation from both genders and members diagnosed as young as late teenage/early 20s. Familial synovial chondromatosis with dwarfism introduces characteristics of dwarfism. Cause
The exact underlying cause of synovial chondromatosis is unknown. Some evidence suggests trauma may play a role in its development as it mainly presents in weight-bearing joints. Infection has also been considered as a contributing factor. The condition is not inherited.Synovial chondromatosis can reportedly occur as either a primary or secondary form. Primary synovial chondromatosis, which is more rare, occurs spontaneously and does not appear to relate to any pre-existing conditions. Secondary synovial chondromatosis is the more common form and often occurs when there is pre-existent osteoarthritis, rheumatoid arthritis, osteonecrosis, osteochondritis dissecans, neuropathic osteoarthropathy (which often occurs in diabetic individuals), tuberculosis, or osteochondral fractures (torn cartilage covering the end of a bone in a joint) in the affected individual. Diagnosis
Diagnosis is by medical imaging; X-ray, CT scan and MRI. For diagnosis of the TMJ, Cone beam computed tomography (CBCT) can also be useful. Treatment
Treatment is frequently by means of removal of the loose bodies and of a partial or full synovectomy (removal of the synovium)
Full synovectomy is a moderately major operation and involves completely exposing the joint and removing the affected tissue. Partial synovectomy is normally done arthroscopically.