[Injection of anaesthetic-corticosteroid to relieve sacroiliac joint pain after lumbar stabilisation].

PURPOSE OF THE STUDY: Both the range of motion and load transfer of the sacroiliac (SI) joint improve considerably after lumbar spine surgery. When, following surgery, SI joint pain develops in spite of appropriate physical therapy, injection of an anaesthetic with added corticosteroid into the SI joint is a first choice treatment. The aim of this presentation is to provide information on our experience with this therapy.

MATERIAL AND METHODS: Thirty-four patients after lumbar spine fusion reported lumbalgia different form pain before surgery. In 14 (41%) of them, pain in one of the SI joints was diagnosed as the cause. This group included 12 women and two men at an average age of 56 (range, 47 to 68) years. Ten patients underwent lumbosacral fixation and four had segmental ("floating") lumbar spine fusion. All patients experienced lumbalgia at more than 3 months following surgery, at 8 months on the average (range, 4 to 12 months). None of them had SI joint pain before surgery. The diagnosis was based on specific manoeuvres on physical examination of the joint. Each patient was given an injection of 20 mg (0.5 ml) Methylprednisolone (Depo-Medrol®, Pfizer, Puurs, Belgium) and 4.5 ml 1% Mesocain (Zentiva, Praha, CR).They were inquired as to pain relief 24 h later and then at 1, 3 and 6 months after injection. Subjective feelings were assessed by a visual analogue scale (VAS). The results were analysed using descriptive statistics.

RESULTS: All patients reported pain relief within 24 h of injection, but not its complete resolution. The average VAS score before and after the blockage of the SI joint was 9.1 points (8-10) and 4.8 points (2-7), respectively; this implies improvement by an average of 4.3 points (1-6), i.e., approximately by 47.3% (12.5-62.5). The duration of effects varied greatly from patient to patient. The average interval between injection and pain recurrence lasted for 5 weeks (1-28). Most frequently, relief was experienced for 2 weeks, or for 6.8 weeks with the standard deviation included. DISCUSSION Sacroiliac joint dysfunction is a very frequent cause of lumbalgia, particularly after lumbar spine surgery. Physical therapy may not always be effective. SI joint arthrodesis is indicated only in rare cases. One of the few possibilities of pain relief involves intra-articular injection of an anaesthetic with corticosteroid for booster effect. The treatment of SI joint blockage after spinal fusion has recently been dealt with in three reports in the international literature; their conclusions are in accordance with the results of this study.

CONCLUSIONS: Lumbar spine stabilisation surgery may result in overloading the SI joints as the "adjacent segments". An intra-articular injection of anaesthetic can be considered a reliable method for ascertaining the SI joint as the source of a patient's problems. However, even with corticosteroid added, pain relief is not usually long-lasting.