Pulmonary‐function testing in children

bruising occurred at portals on other occasions but this resolved rapidly. Haemarthrosis of a minor degree probably occurs frequently, but only one patient in this series developed a tense, painful haemarthrosis which required aspiration of the knee-joint. Significant haemarthrosis has been reported after lateral capsular release under arthroscopic control. 2.3 This procedure involves the division of the lateral capsule and retinaculum of the patella and may be extended proximally. Unavoidably, the superior and inferior lateral genicular vessels or their branches also are divided. In the present series, a modified Metcalf technique was used." The tendinous insertion of the vastus lateralis muscle into the patella was divided, but the vastus lateralis muscle was not detached from the rectus femoris muscle in its distal 75 mm as is recommended by Metcalf. 2 No significant haemarthrosis developed in this series, although minor bruising occurred occasionally. An element of good fortune was present, as Metcalf reported an incidence of haemarthrosis of lOOlo, while McGinty and McCarthy reported a significant incidence of haemarthrosis in approximately 5% of their patients who underwent lateral retinacular release with arthroscopic control. 3 To avoid haemarthroses after operation, some surgeons who are experienced arthroscopists prefer to perform an open operation. This involves a 2.5-cm longitudinal incision that is lateral to the patella at the midpatellar level. This allows the surgeon to divide and to secure the vessels under direct vision. Lateral capsular release then is performed openly without the need for arthroscopic control. The technique that was used in this series was to perform lateral capsular release under arthroscopic control while the tourniquet was inflated. An absorbent rubber-pad of lO mm x 20 mm x 5 mm was placed in a longitudinal direction over the operative site and bandaged firmly to the limb. This allowed bleeding to be controlled by pressure of the pad after the tourniquet was released. Other surgeons use diathermy under arthroscopic control to divide the lateral capsule and the tendinous portion of the vastus lateralis muscle from within the joint and also to coagulate the vessels. Sterile water is used as the medium for diathermy. Another method is to perform arthroscopic lateral capsular release under tourniquet control in the usual way. When the procedure has been completed, the tourniquet is released intermittently and the bleeding vessels are treated by diathermy. Reports of significant haemarthrosis after this procedure cannot be ignored. 2.3 Routine drainage for the first 24-48 h after an operation is recommended, as is the use of diathermy to control bleeding. Blood-grouping should be performed before lateral capsular release. The differential diagnosis of a deep venous thrombosis can be difficult. It can be mimicked by reflex sympathetic dystrophy or by a ruptured synovial cyst. In such circumstances, a vascular surgeon or physician always should be consulted. In cases of deep venous thrombosis all or some of the following clinical features may be present: swelling of the calf; an increase in skin temperature with associated prominent superficial veins; calf tenderness; pain in the calf; and a positive Homan's sign. In the case of a ruptured synovial cyst, swelling of the calf, tenderness of the calf, staining of the skin which occasionally is straw-coloured, and pain in the calf, which develops suddenly, generally are present. Usually, veins are not prominent and Homan's sign is negative. Doppler studies should be performed. These' give abnormal results in cases of deep venous thrombosis. As a result of the Doppler studies, a decision then is made to proceed either to venographic or arthrographic studies. Four cases of deep venous thrombosis occurred in the 100 operative cases from Case 129 to Case 222. The first case occurred after a lateral capsular release, while the next three cases occurred after a meniscectomy. A new protocol then was adopted. Commencing before the operation, calcium heparin (5000 U every 12 hours) was administered. After the operation, an elastic support bandage was applied from the toes to above the knee with maximal pressure at the toes; this was lessened gradually as the bandage became more proximal. Patients were allowed immediate full weight-bearing with crutches merely for balance. As a general anaesthetic agent was administered it usually was about four hours after the operation before walking took place. In the next 192 operative cases, deep venous thromboses did not occur. It is believed that immediate weight-bearing has been the major factor in minimizing the development of this complication. The average tourniquet time for the four patients with deep venous thrombosis and the four patients with causalgia was I h 27 min. This indicated a need to improve expertise so as to minimize the length of the procedure. A tourniquet no longer is used unless excessive bleeding necessitates this. Chondroplasty may be carried out with a motorized instrument which shaves the articular cartilage or, alternatively, can be performed with basket forceps. It originally was believed that the removal of abnormal articular cartilage reduced synovitis in the joint. This view no longer is held universally. The procedure is reserved for the removal of articular cartilage which is causing mechanical interference with joint movement, or which is unstable and has the potential to cause mechanical interference. It is sometimes reasonable "to remove surface debris without trauma to intact layers" " but this may do no more than to reduce the degree of crepitus. In the present series, grade-I complications occurred at the same rate in both the diagnostic and operative groups of arthroscopies. Grade-2 complications were almost twice as common in the operative group than in the diagnostic group while grade-S complications occurred eight times more commonly in the operative group than in the diagnostic group. The over-all complication rate for the diagnostic group was 1.2% and these complications were of minor significance; however, in the operative group the complication rate was 4.3% and of a more-serious nature. It is evident that arthroscopic surgery is not a minor procedure. Every effort should be made to minimize complications in a procedure which is now well-established and which has been of great benefit to many patients.