Rab Mollan

A prospective randomized trial of chemonucleolysis and conventional disc surgery in single level lumbar disc herniation.

The role of chemonucleolysis as an alternative to disc surgery is still disputed. The authors conducted a prospective randomized controlled trial of chemonucleolysis and conventional disc surgery involving 92 patients with L4-5 or L5-S1 disc herniation who failed to respond to conservative treatment. There were 46 patients in each group, matched for demographic, clinical characteristics, and co-interventions. Independent examiners assessed patients before treatment, at 6 weeks after, 3 months after, and 1 year after treatment. A comprehensive method of outcome assessment involving physiological outcome, functional outcome, cost outcome, and psychological outcome was employed. Nine chemonucleolysis patients and one disc surgery patient required additional surgery for failure of initial treatment (P less than 0.02). The outcomes at 6 weeks and at 3 months were better in the surgical group, but at 1 year the differences were not significant. The authors conclude that chemonucleolysis as a minimally invasive technique produces inferior short-term results and offers no advantage over conventional discectomy.

Habitual joint cracking and radiological damage.

A 25 year old Malaysian man who habitually elicited cracking sounds from many of his joints was investigated during a study of joint cracking. He had no symptoms or obvious abnormalities of his joints, but a radiograph of his right hand showed ligamentous ossification on the ulnar side of his third metacarpophalangeal joint and chondrocalcinosis in the first and fourth metacarpophalangeal joints (figure). There was no evidence of osteoarthrosis. Distraction of the articular surfaces during finger pulling lowers =_ the pressure of the synovial fluid. When the vapour pressure is reached the fluid evaporates, giving a cracking sound and forming an intra-articular bubble. Previous studies have reached conflicting conclusions about the radiological changes found in habitual finger cracking, 2 but we suggest that excessive joint cracking may have caused the changes seen in this subject, who had no signs ofany other underlying disease. -P WATSON, A HAMILTON, R MOLLAN, department oforthopaedic surgery, Musgrave Park Hospital, Belfast BT9 77B.

Non-Invasive Diagnosis and Prophylaxis in Orthopaedics

In this paper some ten years of work in bioengineering is described. The central theme is non-invasive diagnosis and prophylaxis. This theme is exemplified in several interrelated sections of work which are described. The work is categorized into: modest beginnings, hip and knee vibration papers, deep venous thrombosis and cavitation in human joints. The philosophy is straightforward—to benefit patients by making harmless measurement.