Aims

Safety concerns surrounding osseointegration are a significant barrier to replacing socket prosthesis as the standard of care following limb amputation. While implanted osseointegrated prostheses traditionally occur in two stages, a one-stage approach has emerged. Currently, there is no existing comparison of the outcomes of these different approaches. To address safety concerns, this study sought to determine whether a one-stage osseointegration procedure is associated with fewer adverse events than the two-staged approach.

Aims. In recent conflicts, most injuries to the limbs are due to blasts resulting in a large number of lower limb amputations. These lead to heterotopic ossification (HO), phantom limb pain (PLP), and functional deficit. The mechanism of blast loading produces a combined fracture and amputation. Therefore, to study these conditions, in vivo models that replicate this combined effect are required. The aim of this study is to develop a preclinical model of blast-induced lower limb amputation. Methods. Cadaveric Sprague-Dawley rats’ left hindlimbs were exposed to blast waves of 7 to 13 bar burst pressures and 7.76 ms to 12.68 ms positive duration using a shock tube. Radiographs and dissection were used to identify the injuries. Results. Higher burst pressures of 13 and 12 bar caused multiple fractures at the hip, and the right and left limbs. Lowering the pressure to 10 bar eliminated hip fractures; however, the remaining fractures were not isolated to the left limb. Further reducing the pressure to 9 bar resulted in the desired isolated fracture of the left tibia with a dramatic reduction in the fractures to other sites. Conclusion. In this paper, a rodent blast injury model has been developed in the hindlimb of cadaveric rats that combines the blast and fracture in one insult, necessitating amputation. Experimental setup with 9 bar burst pressure and 9.13 ms positive duration created a fracture at the tibia with total reduction in non-targeted fractures, rendering 9 bar burst pressure suitable for translation to a survivable model to investigate blast injury-associated diseases. Cite this article: Bone Joint Res 2021;10(3):166–173

Aims. Dystrophic calcification (DC) is the abnormal appearance of calcified deposits in degenerating tissue, often associated with injury. Extensive DC can lead to heterotopic ossification (HO), a pathological condition of ectopic bone formation. The highest rate of HO was found in combat-related blast injuries, a polytrauma condition with severe muscle injury. It has been noted that the incidence of HO significantly increased in the residual limbs of combat-injured patients if the final amputation was performed within the zone of injury compared to that which was proximal to the zone of injury. While aggressive limb salvage strategies may maximize the function of the residual limb, they may increase the possibility of retaining non-viable muscle tissue inside the body. In this study, we hypothesized that residual dead muscle tissue at the zone of injury could promote HO formation. Methods. We tested the hypothesis by investigating the cellular and molecular consequences of implanting devitalized muscle tissue into mouse muscle pouch in the presence of muscle injury induced by cardiotoxin. Results. Our findings showed that the presence of devitalized muscle tissue could cause a systemic decrease in circulating transforming growth factor-beta 1 (TGF-β1), which promoted DC formation following muscle injury. We further demonstrated that suppression of TGF-β signalling promoted DC in vivo, and potentiated osteogenic differentiation of muscle-derived stromal cells in vitro. Conclusion. Taken together, these findings suggest that TGF-β1 may play a protective role in dead muscle tissue-induced DC, which is relevant to understanding the pathogenesis of post-traumatic HO. Cite this article: Bone Joint Res 2020;9(11):742–750

Aims

Heterotopic ossification (HO) is a potentially devastating complication of the surgical treatment of a proximal humeral fracture. The literature on the rate and risk factors for the development of HO under these circumstances is lacking. The aim of this study was to determine the incidence and risk factors for the development of HO in these patients.

Introduction. This study reviews the orthopaedic care of the thirteen patients who were admitted and treated at Royal Manchester Children's' Hospital following the Manchester Arena Bomb blast. Methods. We included all children admitted to Royal Manchester Children's Hospital injured following the bomb blast who either suffered upper limb, lower limb or pelvic fractures, or penetrating upper or lower limb wounds. The nature of each patient's bone and soft tissue injuries, initial and definitive management, and outcome were assessed and documented. Main outcome measures were time to fracture union, time to definitive soft tissue/skin healing, and functional outcome. Findings. Thirteen children were admitted with orthopaedic injuries; 12 were female and mean age was 12.69. All patients had penetrating deep wounds with at least one large nut foreign body in situ, two patients suffered significant burn injury, one patient required amputation of two digits, and two patients required local flap reconstruction. There were a total of 29 upper and lower limb fractures in nine of the patients, with the majority managed without internal or external fixation. In only half of the patients all fractures showed full radiological union at 6 months follow up. There was significant morbidity with several patients suffering long term physical and psychological disability and one patient still in hospital. Conclusion. We found that stable fractures in children secondary to blast injuries can often be appropriately managed without metalwork, and penetrating wounds can be managed without the need for skin graft/flap reconstruction. Our study documents the severe nature of the injuries suffered by paediatric survivors of the Manchester Arena bomb blast. It highlights the demands on a trauma unit following such an event

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

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

Aims

This study describes the Osseointegration Group of Australia’s Accelerated Protocol two-stage strategy (OGAAP-1) for the osseointegrated reconstruction of amputated limbs.

Improve the quality of care mine-explosive wounds and preventing infection in mine blast injury. We have treated 19 patients affected by MEI during Anti-Terrorist Operation (ATO) in Ukraine. The patients had been received by our department within 5–28 days after the injury. All patients were comprehensively examined (general surgeon, neurosurgeon, thoracic surgeon, CT, X-ray, ultrasound, lab tests). 14/19 patients had an open fractures (10 of those 14 had a soft tissue defects). All patients with open fractures underwent secondary surgical treatment (radical debridement, irrigation, ultrasonic cavitation, fracture stabilization by external fixation). The patients with soft tissue defects underwent variety of plastic surgery. After soft tissues healing a plate or IM nail was installed. Evaluation of results was based on X-ray monitoring and the lower limb function assessment. 16 patients had full fracture consolidation and good function, 3 patients had slow consolidation and limitation of movement. Analysis of treatment showed that adherence to radical debridement and thorough soft tissue management led to significant reducing of the incidence of infectious complications in combat related fractures

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.

Scapula fractures mostly occur following high energy trauma, however, the demographics are unknown in deployed soldiers. We analysed the incidence, aetiology, associated injuries, treatment and complications of these fractures in military personnel from Afghanistan and Iraq (2004–2014). Forty-four scapula fractures from 572 upper limb fractures (7.7%) were sustained. 85% were caused by blast or gunshot wounds and 54% were open blast fractures. Multiple injuries were noted including lung, head, vascular and nerve injuries. Injury Severity Scores were almost double compared to the average upper limb injury without a scapula fracture (21 vs. 11). Brachial plexus injuries (17%) have a favourable outcome following GSW compared to blast injuries. Glenoid fractures or floating shoulders were internally fixed (10%) and resulted from high velocity gunshot wounds or mounted blast ejections. There were no cases of deep soft tissue infection or osteomyelitis and all scapula fractures united. Scapula fractures have a 20 times higher incidence in military personnel compared to the civilian population. These fractures are often associated with multiple injuries, including brachial plexus injuries, where those sustained from blast have less favourable outcome. High rates of union following fixation and low rates of infection are expected despite significant contamination and soft tissue loss

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

This is a retrospective study of survivors of recent conflicts with an open fracture of the femur. We analysed the records of 48 patients (48 fractures) and assessed the outcome. The median follow up for 47 patients (98%) was 37 months (interquartile range 19 to 53); 31 (66%) achieved union; 16 (34%) had a revision procedure, two of which were transfemoral amputation (4%).

The New Injury Severity Score, the method of fixation, infection and the requirement for soft-tissue cover were not associated with a poor outcome. The degree of bone loss was strongly associated with a poor outcome (p = 0.00204). A total of four patients developed an infection; two with S. aureus, one with E. coli and one with A. baumannii.

This study shows that, compared with historical experience, outcomes after open fractures of the femur sustained on the battlefield are good, with no mortality and low rates of infection and late amputation. The degree of bone loss is closely associated with a poor outcome.

Cite this article: Bone Joint J 2015;97-B:842–6.

Currently, there is no animal model in which to evaluate the underlying physiological processes leading to the heterotopic ossification (HO) which forms in most combat-related and blast wounds. We sought to reproduce the ossification that forms under these circumstances in a rat by emulating patterns of injury seen in patients with severe injuries resulting from blasts. We investigated whether exposure to blast overpressure increased the prevalence of HO after transfemoral amputation performed within the zone of injury. We exposed rats to a blast overpressure alone (BOP-CTL), crush injury and femoral fracture followed by amputation through the zone of injury (AMP-CTL) or a combination of these (BOP-AMP). The presence of HO was evaluated using radiographs, micro-CT and histology. HO developed in none of nine BOP-CTL, six of nine AMP-CTL, and in all 20 BOP-AMP rats. Exposure to blast overpressure increased the prevalence of HO.

This model may thus be used to elucidate cellular and molecular pathways of HO, the effect of varying intensities of blast overpressure, and to evaluate new means of prophylaxis and treatment of heterotopic ossification.

Cite this article: Bone Joint J 2015;97-B:572–6

Recent evidence suggests that both the accepted mechanism of blast-mediated traumatic amputation (TA) (shockwave then blast wind exposure) and the link with fatal shockwave exposure merit review. Searching UK military prospectively gathered trauma registry data and post mortem CT (PM-CT) records identified casualties from August 2008 to August 2010 with blast-mediated TAs. TA level and associated injuries were recorded. Data on pre-debridement osseous and soft tissue injuries were only consistently available for fatalities through PM-CT imaging. 146 Cases (75 survivors and 71 fatalities) with 271 TAs (130 in survivors and 141 in fatalities) were identified. Through-joint TA rate in fatalities was 34/141 (24.1%). PM-CT analysis demonstrated only 9/34 through joint TAs with contiguous fractures in the immediately proximal long bone/limb girdle. 18/34 had no fracture, and 7/34 had a non-contiguous fracture. The previously reported link between TA and blast lung injury was not present, calling into question the significance of shockwaves in generating blast-mediated TAs. Furthermore, contemporary blast injury theory cannot account for the high prevalence of through joint TAs (previously published rate 1.3%). The proportion of through joint TAs with no associated fracture or a non-contiguous fracture (74%) is supportive of pure flail as a mechanism for blast-mediated TA

A retrospective analysis of all paediatric patients admitted to Camp Bastion Role 3 between June 2006 and March 2013 was conducted from the UK trauma database. Patient demographics, mechanism of injury, anatomical distribution of injury and treatment are described. Two hundred and ninety eight children were admitted, 225 males with a median age of 9 years old. The highest number of cases (78) was recorded in 2011. Overall there were 55 fatalities (85.6% male). Most injuries were by IED (68% of cases) with 74% requiring operative intervention. Seventy-four percent of casualties had three or more anatomical regional injuries. Whilst the most commonly injured region was the lower limb (78%), head injuries were seen in 41%, abdominal injuries in 48% and thorax injuries in 44%. Debridement (including amputations) (59.4%) and laparotomy (30.6%) were the commonest operations performed. Sixty percent of cases were in theatre within one hour of arrival. Amongst survivors the mean ISS score was 17 and amongst fatalities 43; NISS 22 and 51; RTS 5.45 and 2.91. Paediatric blast injuries represent a significant burden to medical facilities in contemporary conflict. Whilst limb injuries predominate, the proportion of head and torso injuries is higher than seen in adult blast injuries

The October 2013 Trauma Roundup³⁶⁰ looks at: Radiological, electromagnetic or just leave it out altogether?: distal locking in intramedullary nailing; Internal fixation of radiation-induced pathological fractures of the femur has a high rate of failure; Obesity and trauma; Short and sweet?: antibiotics in open fractures; Extremity injuries more important than previously thought?; Cement nails tiptop for osteomyelitis; Oxygen measurements for compartment syndrome?

Blast and ballistic weapons used on the battlefield cause devastating injuries rarely seen outside armed conflict. These extremely high-energy injuries predominantly affect the limbs and are usually heavily contaminated with soil, foliage, clothing and even tissue from other casualties. Once life-threatening haemorrhage has been addressed, the military surgeon’s priority is to control infection.

Combining historical knowledge from previous conflicts with more recent experience has resulted in a systematic approach to these injuries. Urgent debridement of necrotic and severely contaminated tissue, irrigation and local and systemic antibiotics are the basis of management. These principles have resulted in successful healing of previously unsurvivable wounds. Healthy tissue must be retained for future reconstruction, vulnerable but viable tissue protected to allow survival and avascular tissue removed with all contamination.

While recent technological and scientific advances have offered some advantages, they must be judged in the context of a hard-won historical knowledge of these wounds. This approach is applicable to comparable civilian injury patterns. One of the few potential benefits of war is the associated improvement in our understanding of treating the severely injured; for this positive effect to be realised these experiences must be shared.

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

The June 2013 Foot & Ankle Roundup³⁶⁰ looks at: soft-tissue pain following arthroplasty; pigmented villonodular synovitis of the foot and ankle; ankles, allograft and arthritis; open calcaneal fracture; osteochondral lesions in the longer term; severe infections in diabetic feet; absorbable first ray fixation; and showering after foot surgery.