Manual of Surgery Volume Second: Extremities—Head—Neck. Sixth Edition.

by Alexis Thomson; Alexander Miles

The patient often complains of pain in the abdomen—which in children may be mistaken for a simple “belly-ache”—and of pain shooting down the buttocks and into the legs. If the cord is pressed upon at the level of the lumbar enlargement the anal and vesical sphincters are paralysed, and the reflexes are exaggerated.

Psoas Abscess.—When an abscess forms, it usually occupies the sheath of the psoas muscle, in which it spreads down towards the iliac fossa, and into the thigh, passing beneath Poupart's ligament, posterior and lateral to the femoral vessels. The communication between the pelvis and the thigh is often very narrow, so that the abscess cavity has to some extent the shape of an hour-glass. The pus may reach the surface in the region of the saphenous opening, or may spread farther down the thigh under cover of the deep fascia. In some cases it is liable to be mistaken for a femoral hernia, as the swelling becomes smaller when the patient lies down, and has an impulse on coughing.

Lumbar Abscess.—Sometimes the pus travels along the posterior branches of the lumbar vessels and nerves to the lateral border of the sacro-spinalis (erector spinæ) and comes to the surface in the space between the edges of the latissimus dorsi and external oblique muscles—the triangle of Petit.

In rare cases it passes through the sacro-sciatic foramen and forms a swelling in the buttock (sub-gluteal abscess); or it may pass through the obturator foramen and reach the adductor region of the thigh or even the perineum.

Lumbo-sacral Region.—Pott's disease in the lumbo-sacral region usually affects adults, and, on account of the breadth of the vertebral bodies and the limited range of movement in this segment of the spine, is seldom accompanied by marked symptoms or deformity. The diagnosis, therefore, is often difficult, unless good skiagrams are available. The disease may be associated with pain in the distribution of the sciatic nerve, which is liable to be mistaken for sciatica. Single or double iliac abscess frequently forms without the patient showing any characteristic signs of spinal disease. When the disease begins in childhood it may induce a permanent deformity of the pelvis, the conjugate diameter at the brim being increased, while the transverse diameter at the outlet is diminished—kyphotic pelvis, and, in females, this may lead to complications in parturition.

Tuberculous Disease of the Sacro-iliac Joint.—This condition may occur as a primary affection, but is much more frequently secondary to disease in the ilium, sacrum, or lower lumbar vertebræ, and is most common in adolescents and young adults of the male sex. It is attended with pain in the lumbar region, and sometimes in the buttock and along the course of the sciatic nerve. The pain is aggravated by movements, especially such as involve sudden and violent contraction of the lumbar and abdominal muscles, for example, coughing, sneezing, or straining during defecation. Tenderness is elicited on making pressure over the joint, on pressing together the iliac bones, or on attempting to abduct the limb while the pelvis is fixed. The muscles of the buttock and thigh are wasted. As any attempt to bear weight on the affected limb causes pain, the patient walks with a limp, and to save the joint he assumes an attitude which is characteristic: he throws his weight on the sound limb, leans forward, using a stick for support, tilts the affected side of the pelvis downwards, and flexes the hip and knee-joints of the diseased limb. The anterior superior spine is unduly prominent on the affected side, and the limb appears to be lengthened. Sooner or later, in most cases, an abscess forms, and the pus may reach the surface over the posterior aspect of the joint. When the pus forms in front of the joint, it may spread laterally in the iliac fossa as an iliac abscess or may gravitate downwards in the hollow of the sacrum and emerge on the buttock through the sacro-sciatic foramen—sub-gluteal abscess. Sometimes it passes into the ischio-rectal fossa or into the perineum. The presence of an abscess in the pelvis may sometimes be recognised on rectal examination. The appearance of an abscess is sometimes the first thing to draw attention to the condition.

As pain across the small of the back and along the course of the sciatic nerve may be among the early symptoms of sacro-iliac disease, the condition is liable to be mistaken for lumbago or for sciatica. From hip disease it is recognisable by noting that the movements of the hip-joint are not restricted. It is not always possible without the aid of skiagrams to differentiate sacro-iliac disease from disease of the lumbar spine, and the two conditions sometimes coexist.

The prognosis is unfavourable, particularly in cases complicated by extensive disease of the ilium with abscess formation and mixed infection.

Treatment.—In early cases the patient should use crutches and wear a patten on the foot of the sound side; in more advanced cases he must be confined to bed, and have absolute rest to the joint secured by means of extension applied to both legs, or by other apparatus. In children a double Thomas' splint or Stiles' abduction frame is a convenient appliance. Counter-irritation by blisters or the actual cautery may be had recourse to in dry cases in which pain is a prominent feature. If operative treatment becomes necessary, as it may, for removal of a sequestrum, access to the seat of disease is obtained by removing the posterior portion of the iliac bone. Cold abscess is treated on the usual lines.

Syphilitic Disease of the Vertebræ.—All the clinical features of Pott's disease may be simulated by gummatous disease of the vertebræ. This is usually met with in adults who have suffered from acquired syphilis; it is most common in the upper cervical vertebræ, and begins on the anterior surface of the bodies. The onset is more sudden than that of tuberculous caries, and the progress more rapid. The bone is early and extensively destroyed, but abscess formation is rare. Severe nocturnal pains are complained of, and some degree of angular deformity may develop. In almost all cases other evidence of tertiary syphilis is present, and this, together with the history and the effects of anti-syphilitic treatment, aids in diagnosis. The local treatment is carried out on the same lines as for tuberculous disease.