32O Anatomy Applied to Medicine and Surgery. 



supplying the hip joint, with the exception of the acces- 

 sory obturator nerve, supply the knee joint as well, viz. : 

 The anterior crural, entering the knee joint, on either side 

 of the patella; the obturator, from behind, through the 

 middle of the posterior ligament; the great sciatic by 

 means of branches that accompany the articular arteries 

 internal, external and azygos hence, pain felt in the 

 knee, at either of these situations, is likely due to the in- 

 volvement of the particular nerve supplying the joint at 

 that point. Barwell draws attention to the sympathy ex- 

 isting between the ends of the bones, so that, when the 

 thigh is pressed upwards, patients often complain of pain, 

 not at the hip joint, but at the knee joint 



Starting pains, inducing night cries, are due to a reflex 

 act through an excited spinal cord, just as the child drops 

 asleep, and when, therefore, the controlling power of the 

 cerebrum is withdrawn. A twitching or an involun- 

 tary relaxation of the over- fatigued muscles, which have 

 kept the limb fixed while the patient was awake, is de- 

 veloped and causes the ends of the diseased bones to come 

 together with sufficient force as to make the child cry out 

 with pain. 



The possibility of hip joint disease should always be 

 kept in mind when examining a patient complaining of 

 pain in the knee joint ; and, in addition to the means usual- 

 ly employed to differentiate disease of the one joint from 

 that of the other, it is well to note, that pressure on the 

 knee will increase the pain if the latter be due to local 

 causes only, but, will not affect it, if it be a referred pain. 

 Abscess in tuberculosis of the hip joint may appear on 

 the surface at any point. When it presents itself in the 

 gluteal region, it may be and frequently is dependent on 

 disease in the head, or in the head and neck of the femur. 

 If appearing above Poupart's ligament, it is, in all likeli- 

 hood, due to perforation of the acetabulum. 



