This work examines the Upper limb (UL) blast-mediated traumatic amputation (TA) significance from recent operations in Afghanistan. It is hypothesized that the presence of an UL amputation at any level is an independent predictor of torso injury. A joint theatre trauma registry search was performed to determine the number of British casualties with TA and their associated injuries. UL TA accounted for 15.7% of all amputations; distributed: shoulder disarticulation 2.5%, trans-humeral 30%, elbow disarticulation 10%, trans-radial 20% and hand 37.5%. The presence of an UL amputation was more likely in dismounted casualties (P=0.015) and is a predictor of an increased number of total body regions injured and thoracic injuries (P 0.001 and P 0.026 respectively). An increased Injury Severity Score (ISS) was seen in patients with multiple amputations involving the UL (UL TA present ISS=30, no UL TA ISS=21; P=0.000) and the ISS was not significantly different whether mounted or dismounted (P=0.806). The presence of an upper limb amputation at any level should insight in the receiving clinician a high index of suspicion of concomitant internal injury; especially thoracic injury. Therefore with regards to blast mediated TA the injury patterns observed reflect a primary and tertiary blast mechanism of injury.
Electron Microscopy and Synchrotron analysis of Heterotopic Ossification (HO) from blast-related amputees' has shown that HO is bone with a disorganised structure and altered remodelling. This research performs mechanical testing of HO to understand its biomechanical properties in an attempt to create an accurate model to predict its morphological appearance. The hypothesis of this work is that HO is mechanically mediated in its formation. Synchrotron mechanical analysis of HO samples was performed to measure Young's modulus, ultimate strength and density distribution. A novel algorithm based on Wolf's law was implemented in a Finite Element (FE) analysis model of HO to take into account the differing mechanical and biological properties measured and the presence of HO outside the skeletal system. An HO modeling factor, which considers boundary conditions, and regulates recruitment of the soft tissue into bone formation, results in a re-creatable formation of HO within the soft tissues, comparable to the appearance of HO seen in military amputees. The results and model demonstrates that certain types of HO are under the control of endogenous and exogenous mechanical stimulus. HO can thus be mechanically exploited in the casualty management and rehabilitation process to achieve better clinical outcomes.
Spinal fractures are common following underbody blast. Most injuries occur at the thoracolumbar junction, and fracture patterns suggest the spine is flexed at the moment of injury. However, current mechanistic descriptions of vertebral fractures are based on low energy injuries, and there is no evidence to correlate fracture pattern with posture at the loading rates seen in blast injury. The T12-L1 segment of 4 human spines was dissected to preserve the paraspinal ligaments and potted in polymethylmecrylate. The specimens were impacted with a 14 kg mass at 3.5m/s in a drop tower; two specimens were impacted in neutral posture, one in flexion, and one in extension. A load cell measured the load history. CT scans and dissection identified the injury patterns. Each specimen sustained a burst fracture. The neutral specimens demonstrated superior burst fractures, the flexed specimen demonstrated a superior burst fracture with significant anterior involvement, and the extended specimen showed a posterior vertebral body burst fracture. At high loading rates, the posture of the spine at the moment of injury appears to affect the resulting fracture. This supports understanding the behaviour of the spine in blast injury and will allow improved mitigation system design in the future.
Severe military pelvic trauma has a high mortality rate with previous work identifying an association between pelvic fracture and traumatic amputation (TA) of the lower limb (LL). Research has also identified casualties with this combination of injuries as the potential ‘future unexpected survivors’, however, most casualties die early from exsanguination, often before medical interventions can be performed. Therefore targeting injury prevention or mitigation might be the route to increased survivorship. This study investigates this combination of injury and identifies targets for preventative techniques. A search of the JTTR from 2003 to 2014 identified all patients with TA and all pelvic fractures. Of 989 casualties with LL TAs, 19% had an associated pelvic fracture, and this was associated with a 56% mortality rate compared to 24% without. Both pubic symphysis and sacroiliac separation alike were associated positively with traumatic amputation (p < 0.01). The combination of pelvic instability and TA had a mortality rate of 52%. We hypothesise that pelvic fracture may share a mechanistic link with TA, meaning fracture may occur as a consequence of the force and direction of the TA, and it may be possible to direct mitigation strategies at this injury in order to improve survival rates.
The lower limbs of vehicle occupants are vulnerable to severe injuries during under vehicle explosions. Understanding the injury mechanism and causality of injury severity could aid in developing better protection. Therefore, we tested three different knee positions in standing occupants (standing, knee in hyper-extension, knee flexed at 20˚) of a simulated under‐vehicle explosion using cadaveric limbs in a traumatic blast injury simulator; the hypothesis was that occupant posture would affect injury severity. Skeletal injuries were minimal in the cadaveric limbs with the knees flexed at 20˚. Severe, impairing injuries were observed in the foot of standing and hyper‐extended specimens. Strain gauge measurements taken from the lateral calcaneus in the standing and hyper-extended positions were more than double the strain found in specimens with the knee flexed position. The results in this study demonstrate that a vehicle occupant whose posture incorporates knee flexion at the time of an under‐vehicle explosion is likely to reduce the severity of lower limb injuries, when compared to a knee extended position.
Conflict in Afghanistan demonstrated predominantly lower extremity and pelvi-perineal trauma secondary to Improvised Explosive Devices (IEDs). Mortality due to pelvic fracture (PF) is usually due to exsanguination. This study group comprised 169 military patients who sustained a PF and lower limb injury. There were 102 survivors and 67 fatalities (39% mortality). Frequent fracture patterns were a widened symphysis (61%) and widening of the sacroiliac joints (SIJ) (60%). Fatality was 20.7% for undisplaced SIJs, 24% for unilateral SIJ widening and 64% fatality where both SIJs were disrupted, demonstrating an increase in fatality rate with pelvic trauma severity. A closed pubic symphysis was associated with a 19.7% mortality rate versus 46% when widened. Vascular injury was present in 67% of fatalities, versus 45% of survivors. Of PFs, 84% were associated with traumatic amputation (TA) of the lower limb. Pelvic fracture with traumatic lower limb amputation presents a high mortality. It is likely that the mechanism of TA and PF are related, and flail of the lower limb(s) is the current hypothesis. This study prompts further work on the biomechanics of the pelvic-lower limb complex, to ascertain the mechanism of fracture. This could lead to evidence-based preventative techniques to decrease fatalities.
The explosive device has successfully been used by terrorists globally, with their effects extending beyond the resulting injuries. Suicide bombings, in particular, are being increasingly deployed due to the devastating effect of a combination of, high lethality and target accuracy. This aim of this study was to analyse the demographics and casualty figures of terrorist bombings worldwide. Analysis of the Global Terrorism Database and a PubMed search (keywords “terrorist”, and/or “suicide”, and/or “bombing”) from 1970 to date was performed. Of 58,095 reported terrorist explosions worldwide, 5.08% were suicide bombings. Incidents per year is increasing (P<0.01). PubMed identified 41 publications reporting 167 incidents. Mean casualty statistics per incidents was 1.14 deaths and 3.45 wounded from non-suicide incidents, and 10.16 and 24.16 from suicide bombings (p<0.05). The Middle East witnessed the most incidents (26.9%), with Europe ranked 4th in the number of terrorist related explosion (13.2%). Differing injury patterns were seen in open, confined and building collapse incidents. Terrorist bombings continue to be a threat and are increasing in the Middle East and Europe. Suicide bombings are becoming an increased threat with greater casualty figures per incident seen. This data assists in the planning of security, logistics, casualty evacuation and care.
Heterotopic ossification (HO) is the formation of lamellar bone in extra-skeletal soft tissues. Its exact pathogenic mechanism remains elusive. Previous studies demonstrate observation only of HO at the microscopic scale. This study uses scanning electron microscopy (SEM), Back-scatter electron (BSE) imaging and mechanical testing to detail the organic and non-organic elements of HO, compared to normal bone, to guide stem cell and bio-modelling research into HO. Samples analysed were 5 military blast related HO patients, 5 control cadaveric samples (age and sex matched). Samples were imaged using SEM, BSE and the I13 beam Synchrotron x-ray diffraction scanner using validated quantitative and qualitative techniques of measurement. Appearances seen in HO compared to normal bone were characterised by the presence of a hyper-vascular network and high lacunae (osteocyte) counts, two distinct zones of bone mineral density distribution, with a tendency for hypermineralisation with kurtosis of the grey scale plots (mineral content as a weight percentage of Ca2+ was calibrated to atomic weight of C, Al and HA). Direction of dependence and collagen orientation in HO suggest isotropic properties. This research demonstrates that HO is bone, however its characteristics suggest a high metabolic turnover and disorganised ultra-structure consistent with an inflammatory origin.
Previous reports of the prevalence of Heterotopic Ossification (HO) in limbs from UK blast-related amputees from Afghanistan, is demonstrated to be 57.1%. With the end of UK military operations in Afghanistan in 2014 the aim of this study is establish the rate of HO, assess causality demographics and ascertain risk factors for the formation of HO during the entire period of operations in Afghanistan. Military databases, case notes and radiographs were scrutinised to quantify and qualify the prevalence and risk factors for the formation of HO. 256 servicemen sustained 398 military trauma related amputations. The overall prevalence of HO was 65.9%. Significant (p<0.05) risks identified for the formation of HO included a blast mechanism of injury, a zone of injury the same as the subsequent amputation, and an increased number of debridements prior to closure. Positive correlation existed between the number of amputations and the presence and grade of HO (p=0.04). HO presents clinical problems to military blast injury patient populations. This study demonstrates that both a blast mechanism of injury and an increased injury load are key factors in the increased prevalence of HO seen in military trauma.
Military personnel operating on high speed marine craft are exposed to Whole-Body Vibration (WBV). Additionally planing craft operate at speeds with minimal contact of the hull with warer making the crew vulnerable to mechanical shock. An association between Low Back Pain (LBP) and exposure to WBV has been extensively reported in civilian literature. LBP is reported by military personnel operating on planing craft leading to downgrades and potential discharge. There is a clear need to understand the impact prolonged exposure has on our population operating these craft. We performed a bibliographical search of the PubMed database for records using a combination of keywords. Abstracts were screened for relevance and references cited in retrieved papers reviewed. There is no consensus in the literature on the potentially pivotal pathological process behind the association. Evidence from professional driving suggests current safe operating exposure levels require review to protect against long-term damage however with little evidence concerning the unique environment in which boats crews operate, the parity of these environments require investigation to allow direct comparison. Due to the prevalence of LBP in this population a need exists to establish the pathological process and add to the evidence base driving safe operating exposure levels.
A randomised controlled trial was conducted using a rabbit model of a complex contaminated extremity war wound. Compared to saline soaked gauze dressings Inadine (iodine) and Acticoat (nanocrystalline silver) had significantly lower levels of Molecular level analysis of the wound was conducted. Plasma cytokines of interest were assayed using ELISA and levels of expression of relevant tissue genes measured using PCR following RNA extraction. Appreciable levels of Interleukins 4 and 6 and Tumour Necrosis Factor-α were identified in plasma with significantly higher levels of IL-4 and TNFα detected in the Activon Tulle group. In tissue TNFα, Matrix metalloproteinase-3 and the ratio of Matrix metalloproteinase-9 to Tissue Inhibitor of Matrix metalloproteinase-1 were significantly higher in tissue injured limbs than the uninjured limbs with no significant differences between groups. Interpretation of these results is challenging. IL-4 has been associated with transition from pathological inflammation to repair and TNFα with impaired healing. However, Activon Tulle had significantly higher levels of
Conflict in the Middle East has seen a change in warfare tactics from the use of ballistic missiles to blast weapons. This has resulted in a change in wounding patterns. Due to the severity of the injuries, there have been large numbers of amputations, as life and limb saving procedures. The purpose of this paper was to retrospectively review all the amputated limbs over the past 8 years of conflict and compare those from the early years to the more recent ones. In particular, the aim was to examine differences in the mechanisms of injury, number of limbs injured, associated injuries, method of amputation, microbiology of contaminating organisms and outcome. There were significantly more amputations, injured limbs and soft tissue perineal wounds as well as a significantly higher ISS in the later group. There were also significant differences in the surgical techniques, with more guillotine amputations in the early group, and mechanism of injury, with more blast injuries in the late group. This confirms the clinical impression that there has been a significant change in limb trauma from Iraq to Afghanistan. These injury patterns have significantly different logistical implications, which must be considered when planning the required medical assets in future conflicts.
Published infection rates following wounds sustained in combat vary dramatically. We reviewed UK military extremity trauma, sustained in Afghanistan over a two year period, to evaluate early infection rates and causative organisms. Data on wound site, time to onset of infection, organisms detected and method of presentation were collected. 351 patients had full datasets for clinical wound surveillance and microbiological data. 58 (16.5%) patients were diagnosed with wound infections. Median time to diagnosis was 17 days (range = 749, Interquartile range =31.75 days). Limb infection was detected in 53 (15.1%) patients. Infection was statistically significantly more likely to be incurred in the lower extremity (p=0.0220). Multiple organisms were identified in 34 (64.2%) of the 53 patients with a limb infection. Fungi were significantly more common in early presenters (<30 days after injury) (p=0.0024). The overall infection rates recorded are low when compared to historical data. Organisms isolated from infected wounds are frequently multiple. The microbial spectrum and the number of organisms present on diagnosis change with time from wounding.
Traumatic amputations (TAs) are amongst the most significant orthopaedic sequelae following IED strikes. Biomechanically, longer residual limb length confers better function. However, post-trauma definitive through knee amputation (TKA) remains controversial. UK military casualties sustaining ≥1 major TA, 01/08/2008–01/08/2010 were identified using the UK JTTR and post mortem CT databases. All through- and below-knee TAs were termed ‘potential TKAs’ (p-TKAs); hypothetical candidates for definitive TKA. We hypothesised that traumatic TKAs were more common than previously reported (4.5% of lower limb TAs) and a significant cohort of blast injuries exist suitable for definitive TKA. 146 cases (75 survivors, 71 fatalities) sustained 271 TAs (235 lower limb). TKA rate was 34/235 (14.2%). 63/130 survivor TAs and 66/140 fatality TAs merited analysis as p-TKAs. Detailed pathoanatomy was only available for fatality p-TKAs, for whom definitive TKA would have been proximal to the zone of injury (ZOI) in only 3/66 cases. Blast-mediated traumatic TKAs are significantly more common than previously reported (
With the drawdown from Afghanistan focus turns towards future operations, and their demands on the DMS. Training for surgeons deploying to military operations will have to take into account the decreased opportunities and experience gained by current conflicts. The aim is to focus on current UK surgical training for military operations specifically. A comparison is made with US surgical training. A questionnaire was distributed to UK military surgical consultants in General Surgery, Trauma and Orthopaedics and Plastic Surgery. A similar questionnaire was sent to deployed US surgeons in SE Afghanistan. Response rates of 55% were achieved. Respondents were questioned on their confidence to perform several key procedures. Most UK consultants were satisfied with their overall training for deployment. Satisfaction rates were high for the MOST course and Danish Surgery. US satisfaction with pre-deployment training was poor. The majority of respondents felt confident to perform all haemorrhage and contamination control procedures in an emergency. However, most felt training for military personnel should be lengthened by a year or more to include greater exposure to other specialties. Whilst satisfaction with surgical training is high, many UK surgeons appear to suggest an increase in specialty exposure in preparation for future deployments.
The accepted mechanism of traumatic limb amputation following blast is initial bone disruption due to the shock wave, with amputation completed by the blast wind; survival is considered unlikely. The high survival rate of traumatic amputees following explosion, from the current conflict in Afghanistan, is at odds with previous work. We reviewed extremity injuries, sustained in Afghanistan by UK military personnel, over a 2 year period. 774 British servicemen and women sustained AIS >1 injuries, 72.6% of whom survived. No significant difference was found in the survival rates following explosive blast or gunshot (p>0.05). 169 casualties (21.8%) sustained 263 lower limb and 74 upper limb traumatic amputations. Amputations were more common in the lower than the upper limbs and more common in the extremity proximal bone. Bilateral lower limb amputations were more common than a unilateral lower limb amputation. The majority (99%) of major amputations were sustained as a result of explosion. 46.3% (74) of those who sustained a major amputation following explosion survived. Rates of fatalities caused by explosion, or by small arms are not statistically different. Blast-mediated amputations are not universally fatal, and a significant number were through joint, calling into question previously proposed mechanisms.
The conflict in Afghanistan has been epitomised by the emergence of the Improvised Explosive Device(IEDs). Improvements in medical treatments have resulted in increasing numbers of casualties surviving with complex lower extremity injuries. To date, there has been no analysis of foot and ankle blast injuries as a result of IEDs. Therefore the aims of this study are to firstly report the pattern of injury and secondly determine which factors were associated with a poor clinical outcome in order to focus future research. Using a prospective trauma registry, UK Service Personnel who sustained lower leg injuries following an under-vehicle explosion between Jan 2006 and Dec 2008 were identified. Patient demographics, injury severity, the nature of lower limb injury and clinical management was recorded. Clinical endpoints were determined by (i)need for amputation and (ii)need for ongoing clinical output at mean 33.0 months follow-up. 63 UK Service Personnel (89 injured limbs) were identified with lower leg injuries from explosion. 50% of casualties sustained multi-segmental injuries to the foot and ankle complex. 26(29%) limbs required amputation, with six amputated for chronic pain 18 months following injury. Regression analysis revealed that hindfoot injuries, open fractures and vascular injuries were independent predictors of amputation. Of the 69 limbs initially salvaged, the overall infection rate was 42%, osteomyelitis 11.6% and non-union rates was 21.7%. Symptomatic traumatic osteoarthritis was noted in 33.3% salvaged limbs. At final follow-up, 66(74%) of injured limbs had persisting symptoms related to their injury, with only 9(14%) fit to return to their pre-injury duties. This study demonstrates that foot and ankle injuries from IEDs are frequently associated with a high amputation rate and poor clinical outcome. Although, not life-threatening, they remain a source of long-term morbidity in an active population. Primary prevention of these injuries remain key in reducing the injury burden.
A randomised controlled pre-clinical trial utilising an existing extremity war wound model compared the efficacy of saline soaked gauze to commercial dressings. The Flexor Carpi Ulnaris of anaesthetised New Zealand rabbits was exposed to high-energy trauma using computer-controlled jig and inoculated with 106 Clinical observations and haematology were performed during the study. Histopathological assessment of post-mortem muscle specimens included image analysis of digitally scanned haematoxylin and eosin stained tissue sections and subjective semi-quantitative assessment of pathology severity using light microscopy to grade muscle injury and lymph node activation. Tissue samples were also examined using scanning electron microscopy to determine the presence of bacteria and biofilm formation within the injured muscle. Non-parametric data were compared using Kruskal-Wallis. There were no bacteraemias, significantly raised white cell counts, abscesses, purulent discharge or evidence of contralateral axillary lymph node activation. All injured muscle specimens showed evidence of haemorrhage, inflammatory cell infiltration and fibrosis. All ipsilateral axillary lymph nodes were activated. There were no significant differences in the amount of muscle loss, size of the activated lymph nodes or in subjective semi-quantitative scoring criteria for muscle injury or lymph node activation. There was no evidence of bacterial penetration or biofilm formation. This study demonstrated statistically significant reductions in
Circumferential pelvic binders have been developed to allow rapid closure of the pelvic ring in unstable fracture patterns. Despite evidence to support the use of pelvic binders, there is a paucity of clinical data regarding the effect of binder position on symphyseal diastasis reduction. All patients presenting to the UK's military hospital in Afghanistan who survived and underwent pelvic radiography were reviewed. Cases were identified by retrospective assessment of all digital plain pelvic radiographs performed between January 2008 and July 2010. All radiographs and CT images were assessed to identify the presence of any pelvic fracture. Patients were grouped into three categories according to the vertical level of the buckle: superior to the trochanters (high), inferior to the trochanters (low) and at the level of the trochanters (troch). Diastasis reduction was measured in patients with Anterior-Posterior Compression (APC) grades II and III, or Combined Mechanical Injuries(CMI). Comparison of diastasis reduction between the high and troch groups was assessed by an independent samples Student's t-test. We identified 172 radiographs where the metallic springs in the buckle of a SAM Pelvic Sling™ were clearly visible. The binders were positioned at the trochanteric level in 50% of radiographs. A high position was the commonest site of inaccurate placement (37%). In the patients with fractures and an open diastasis, the mean pelvic diastasis gap was 2.75 times greater in the high group compared to the trochanteric level (mean difference 22 mm) (p < 0.01). Application of pelvic binders superior to the greater trochanters is commonplace and associated with inadequate fracture reduction, which is likely to delay cardiovascular recovery in these significantly injured casualties.
Peripheral nerve injuries (PNI) occur in 10% of combat casualties. In the immediate field-hospital setting, an insensate limb can affect the surgeon's assessment of limb viability and in the long-term PNI remain a source of considerable morbidity. Therefore the aims of this study are to document the recovery of combat PNI, as well as report on the effect of current medical management in improving functional outcome. In this study, we present the largest series of combat related PNI in Coalition troops since World War II. From May 2007 – May 2010, 100 consecutive patients (261 nerve injuries) were prospectively reviewed in a specialist PNI clinic. The functional recovery of each PNI was determined using the MRC grading classification (good, fair and poor). In addition, the incidence of neuropathic pain, the results of nerve grafting procedures, the return of plantar sensation, and the patients' current military occupational grading was recorded. At mean follow up 26.7 months, 175(65%) of nerve injuries had a good recovery, 57(21%) had a fair recovery and 39(14%) had a poor functional recovery. Neuropathic pain was noted in 33 patients, with Causalgia present in 5 cases. In 27(83%) patients, pain was resolved by medication, neurolysis or nerve grafting. In 35 cases, nerve repair was attempted at median 6 days from injury. Of these 62%(22) gained a good or fair recovery with 37%(13) having a poor functional result. Forty-two patients (47 limbs) initially presented with an insensate foot. At final follow up (mean 25.4 months), 89%(42 limbs) had a return of protective plantar sensation. Overall, 9 patients were able to return to full military duty (P2), with 45 deemed unfit for military service (P0 or P8). This study demonstrates that the majority of combat PNI will show some functional recovery. Adherence to the principles of war surgery to ensure that the wound is clear of infection and associated vascular and skeletal injuries are promptly treated will provide the optimal environment for nerve recovery. Although neuropathic pain affects a significant proportion of casualties, pharmacological and surgical intervention can alleviate the majority of symptoms. Finally, the presence of an insensate limb at initial surgery, should not be used as a marker of limb viability. The key to recovery of the PNI patient lies in a multi-disciplinary approach. Essential to this is regular surgical review to assess progress and to initiate prompt surgical intervention when needed. This approach allows early determination of prognosis, which is of huge value to the rehabilitating patient psychologically, and to the whole rehabilitation team.
