Primary lateral sclerosis (PLS) is a very rare neuromuscular disease characterized by progressive muscle weakness in the voluntary muscles. PLS belongs to a group of disorders known as motor neuron diseases. Motor neuron diseases develop when the nerve cells that control voluntary muscle movement degenerate and die, causing weakness in the muscles they control. PLS only affects upper motor neurons. There is no evidence of the degeneration of spinal motor neurons or muscle wasting (amyotrophy) that occurs in amyotrophic lateral sclerosis (ALS). Symptoms and signs
Onset of PLS usually occurs spontaneously after age 50 and progresses gradually over a number of years, or even decades. The disorder usually begins in the legs, but it may start in the tongue or the hands. Symptoms may include difficulty with balance, weakness and stiffness in the legs, and clumsiness. Other common symptoms are spasticity (involuntary muscle contraction due to the stretching of muscle, which depends on the velocity of the stretch) in the hands, feet, or legs, foot dragging, and speech and swallowing problems due to involvement of the facial muscles. Breathing may also become compromised in the later stages of the disease, causing those patients who develop ventilatory failure to require noninvasive ventilatory support. Hyperreflexia is another key feature of PLS as seen in patients presenting with the Babinskis sign.
Pelvic floor dysfunction and its multiple consequences, including urinary incontinence, is a concerning health issue becoming more evident as the population of advancing age individuals rises. Causes
Mechanistically, the causes of pelvic floor dysfunction are two-fold: widening of the pelvic floor hiatus and descent of pelvic floor below the pubococcygeal line, with specific organ prolapse, graded relative to the hiatus. People with an inherited deficiency in their collagen type may be more likely to develop pelvic floor dysfunction. Additionally, people with congenitally weak connective tissue and fascia are at an increased risk for stress urinary incontinence and pelvic organ prolapse. Recent literature demonstrates that defects in endopelvic fascia and compromised levator ani muscle function have been categorized as important etiologic factors in the development of pelvic floor dysfunction. Some circumstances are clearly associated with collagen defects. These include vaginally delivering a child, being post-menopausal, and being of advanced age.Some lifestyle behaviors can lead to pelvic floor dysfunction. This includes avoiding urinating or bowel movements, obesity, use of muscle relaxants or narcotics, and use of antihistamines or anticholinergics. Using muscle relaxants or narcotics can lead to increased smooth and skeletal muscle relaxation, potentially related to urinary incontinence. Antihistamines and anticholinergics have additive effects that lead to urinary hesitancy and retention, ultimately leading to pelvic floor dysfunction. Urinary incontinence can also affect athletes, especially those in sports that require high impact such as jumping. Gymnasts, for example, report a high prevalence of urinary incontinence.