Improvised Explosive Device (IED) attacks on vehicles have been a significant feature of recent conflicts. The Dynamic Response Index (DRI), developed for predicting spinal injury in aircraft ejection, has been adopted for testing vehicles in underbelly blast. Recent papers suggest that DRI is not accurate in blast conditions. We suggest that the distribution of blast and ejection injuries is different. A literature review identified the distribution of spinal fractures in aircraft ejection incidents. A Joint Theatre Trauma Registry search identified victims of mounted IED blast with spinal fractures. The distribution of injuries in the two groups was compared using the Kruskall Wallis test. 329 fractures were identified in ejector seat incidents; 1% cervical, 84% thoracic and 16% lumbar. 245 fractures were identified in victims of mounted blast; 16% cervical, 34% thoracic and 50% lumbar. There was no significant similarity between the two (p=1). There was no statistically significant difference between the distribution of fractures in blast survivors versus fatalities. The difference between blast and ejection injury patterns suggests that injury prediction models for ejection should not be extrapolated to blast mechanisms and that new models need to be developed.
The Global Conservative Anatomic Prosthesis (Global CAP) is an uncemented press fit humeral resurfacing implant developed by DePuy. We report a single surgeon series of Global CAP prostheses implanted in Norwich. 103 procedures were carried out between 2006 and 2011, in 93 patients. Mean age was 72 years (range 43 to 90). Patients were followed up for a mean 8 months (range 0 to 56). Pre-operative Oxford shoulder scores were recorded in a preadmission clinic and an Oxford score questionnaire was sent to patients post-operatively in December 2011. The mean score preoperatively was 19, rising to 28 postoperatively. Two patients developed rotator cuff tears and have been revised to reverse polarity arthroplasty. One is pending revision for a cuff tear. This prosthesis shows promise at this early stage for compensated glenohumeral arthritis when a bone preserving procedure is desirable.
