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Aim: To compare the radiation dose of cervical spine clearance and body CT in a cohort of unconscious, major trauma patients for three different protocols, comparing spiral to multislice CT. To quantify the radiation exposure effect of the protocols on the lifetime cancer risk. Method: The hospital trauma database was used to find the unconscious (GCS<9), severely injured (Injury Severity Score >15) from 1 January 2001 to 31 December 2003, excluding isolated head injuries. The protocols used for imaging the brain and cervical spine were, including the radiographs performed as a mode: The exposure factors and field of view used were put into the Monte Carlo software, to estimate the CT and radiographic X-ray doses to the body as a whole and the dose to the thyroid associated with each region imaged. The associated nominal additional lifetime cancer risk was assessed. Results: Excluding inter hospital transfers, where data was incomplete, 87 patients survived to be admitted and fulfilled the criteria. In 30 cases, the CT films were missing, the exposure factors were not recorded or no imaging was performed. In a further 21 cases, the X-ray packets were missing. Three patients had brain and cervico-dorsal CT imaging only, leaving 33 cases for evaluation. The effective radiation dose for a spiral CT of the brain using the Toshiba Xpress GX CT scanner was 3.8 mSv. The total effective doses for imaging the brain and cervical spine using the three protocols with the same CT scanner were (S.D. as % of mean): (1) 4.4 mSv (5%), (2) 7.1 mSv (10%) and (3) 8.2 mSv (15%). The corresponding mean thyroid doses were: (1) 8.5 mGy (25%), (2) 48.9 mGy (20%) and (3) 66.5 mSv (20%). The resultant nominal lifetime cancer risks were: (1) 1:4500, (2) 1:2800 and (3) 1:2400. For the Siemens Sensation 16 multislice CT scanner, the total effective doses (S.D. as % of mean) were: (1) 2.3 mSv (10%), (2) 4.3 mSv (25%) and (3) 5.4 mSv (35%). The mean doses to the thyroid were: (1) 5.9 mGy (30%), (2) 36.1 mGy (50%) and (3) 52.4 mGy (40%). The lifetime cancer risks were: (1) 1:8700, (2) 1:4600 and (3) 1:3700. Using the Toshiba spiral CT scanner, the total dose and additional lifetime nominal cancer risk associated with CT of the chest, abdomen and pelvis (CAP) as 16 mSv and 1:1250, respectively. Using the Siemens multislice CT scanner, these were 11.8 mSv and 1:1700. The cancer risk for protocol 1 when combined with a CT scan of the chest, abdomen and pelvis was 1:1000 for the spiral CT scanner and 1:1500 for the multislice CT (MCT) scanner. The cancer risk for protocol 2 with CAP CT using the MCT was 1:1200. The cancer risk for protocol 3 when combined with a CT scan of the chest, abdomen and pelvis was 1:1100 for the multislice CT scanner. Prior to the introduction of the BTS guidelines for cervical clearance, 12% of cases had CT of the body, which increased to 16% post-guidelines. Conclusions: CT of the trunk (chest, abdomen and pelvis) is associated with the greatest risk of inducing a fatal cancer in the severely injured patient with a GCS less than 9. In our institution the multislice CT protocols expose the patient to less radiation than single slice CT, which is contrary to much of the published work to date. CT scanning the thyroid (or whole cervical spine) still has a marked effect on the cancer risk in cervical clearance. Many centres will relax cervical spinal precautions in unconscious trauma patients if the cervical spine CT with reconstructions is normal. CT of the whole cervical spine may be justified in the unconscious, severely injured patient. In conscious trauma patients, the additional lifetime risk may not justify CT of the whole cervical spine as a routine practice. [ABSTRACT FROM AUTHOR]

Ethical concerns have hindered any randomised control blinded studies on the imaging required to assess the cervical spine in an unconscious trauma patient. The issue has been contentious for many years and has resulted in burgeoning but inconclusive guidance. MRI and multislice CT technology have made rapid advances, but the literature is slower to catch up. Never the less there appears to be an emerging consensus for the multiply injured patient. The rapid primary clinical survey should be followed by lateral cervical spine, chest and pelvic radiographs. If a patient is unconscious then CT of the brain and at least down to C3 (and in the USA down to D1) has now become routine. The cranio-cervical scans should be a maximum of 2 mm thickness, and probably less, as undisplaced type II peg fractures, can be invisible even on 1 mm slices with reconstructions. If the lateral cervical radiograph and the CT scan are negative, then MRI is the investigation of choice to exclude instability. Patients with focal neurological signs, evidence of cord or disc injury, and patients whose surgery require pre-operative cord assessment should be imaged by MRI. It is also the investigation of choice for evaluating the complications and late sequela of trauma. If the patient is to have an MRI scan, the MR unit must be able to at least do a sagittal STIR sequence of the entire vertebral column to exclude non-contiguous injuries, which, since the advent of MRI, are now known to be relatively common. Any areas of oedema or collapse then require detailed CT evaluation. It is important that cases are handled by a suitably skilled multidisciplinary team, and avoid repeat imaging due to technical inadequacies. The aim of this review is to re-examine the role of cervical spine imaging in the context of new guidelines and technical advances in imaging techniques.

The aim of this study was to assess the radiological evaluation of all prospective, randomised, controlled trails of displaced intraarticular calcaneal fractures. A systematic review of the literature, of which only three of 296 references were randomised and controlled, were examined in a blinded fashion. All had preoperative coronal CT for Sander's classification and used a lateral surgical approach or conservative treatment. Thordason (15 patients/11 controls) used interoperative lateral and axial X-rays. Bohler's angle increased on average from 11 to 26 degrees (P<0.001) postoperatively, but decreased (9-8 degrees ) in the conservative group. The posterior facet residual displacement was 1.1 and 4.7 mm, respectively. O'Farrell (12 patients/12 controls) showed 8 out of 12 had Bohler's and Gissane's angle partially or fully restored postoperatively, and not conservatively. Parmar (25 patients/31 controls) used preoperative lateral radiographs, but failed with CT to grade the postoperative reduction, whilst the conservative group was unaltered. There was no systematic, blinded assessment of the change in radiology by the operative intervention. Overall there was weak evidence to support ORIF. In conclusion, there are only three randomised, controlled studies involving small numbers of patients, which showed improved plain radiographic anatomical alignment, in the postoperative but not conservative group. Further prospective randomised, controlled trials with independent and blinded assessment with accurate CT and clinical evaluation will be required before ORIF can be adopted as the best practice.