Aims

The purpose of this study was to develop a convolutional neural network (CNN) for fracture detection, classification, and identification of greater tuberosity displacement ≥ 1 cm, neck-shaft angle (NSA) ≤ 100°, shaft translation, and articular fracture involvement, on plain radiographs.

Aims

The primary aim of this study was to develop a reliable, effective radiological score to assess the healing of humeral shaft fractures, the Radiographic Union Score for HUmeral fractures (RUSHU). The secondary aim was to assess whether the six-week RUSHU was predictive of nonunion at six months after the injury.

This article presents a unified clinical theory that links established facts about the physiology of bone and homeostasis, with those involved in the healing of fractures and the development of nonunion. The key to this theory is the concept that the tissue that forms in and around a fracture should be considered a specific functional entity. This ‘bone-healing unit’ produces a physiological response to its biological and mechanical environment, which leads to the normal healing of bone. This tissue responds to mechanical forces and functions according to Wolff’s law, Perren’s strain theory and Frost’s concept of the “mechanostat”. In response to the local mechanical environment, the bone-healing unit normally changes with time, producing different tissues that can tolerate various levels of strain. The normal result is the formation of bone that bridges the fracture – healing by callus. Nonunion occurs when the bone-healing unit fails either due to mechanical or biological problems or a combination of both. In clinical practice, the majority of nonunions are due to mechanical problems with instability, resulting in too much strain at the fracture site. In most nonunions, there is an intact bone-healing unit. We suggest that this maintains its biological potential to heal, but fails to function due to the mechanical conditions. The theory predicts the healing pattern of multifragmentary fractures and the observed morphological characteristics of different nonunions. It suggests that the majority of nonunions will heal if the correct mechanical environment is produced by surgery, without the need for biological adjuncts such as autologous bone graft.

Cite this article: Bone Joint J 2016;98-B:884–91.

We retrospectively reviewed 2989 consecutive patients with a mean age of 81 (21 to 105) and a female to male ratio of 5:2 who were admitted to our hip fracture unit between July 2009 and February 2013. We compared weekday and weekend admission and weekday and weekend surgery 30-day mortality rates for hip fractures treated both surgically and conservatively. After adjusting for confounders, weekend admission was independently and significantly associated with a rise in 30-day mortality (odds ratio (OR) 1.4, 95% confidence interval (CI) 1.02 to 1.9; p = 0.039) for patients undergoing hip fracture surgery. There was no increase in mortality associated with weekend surgery (OR 1.2, 95% CI 0.8 to 1.7; p = 0.39). All hip fracture patients, whether managed surgically or conservatively, were more likely to die as an inpatient when admitted at the weekend (OR 1.4, 95% CI 1.02 to 1.80; p = 0.032), despite our unit having a comparatively low overall inpatient mortality (8.7%). Hip fracture patients admitted over the weekend appear to have a greater risk of death despite having a consultant-led service.

Cite this article: Bone Joint J 2014;96-B:373–8.

Isolated fractures of the anterior column and anterior wall are a relatively rare subgroup of acetabular fractures. We report our experience of 30 consecutive cases treated over ten years. Open reduction and internal fixation through an ilioinguinal approach was performed for most of these cases (76.7%) and percutaneous techniques were used for the remainder. At a mean follow-up of four years (2 to 6), 26 were available for review. The radiological and functional outcomes were good or excellent in 23 of 30 patients (76.7%) and 22 of 26 patients (84.6%) according to Matta’s radiological criteria and the modified Merlé d’Aubigné score, respectively.

Complications of minor to moderate severity were seen in six of the 30 cases (20%) and none of the patients underwent secondary surgery or replacement of the hip.

We investigated the excess mortality risk associated with fractures of the hip. Data related to 29 134 patients who underwent surgery following a fracture of the hip were obtained from the Scottish Hip Fracture Audit database. Fractures due to primary or metastatic malignancy were excluded. An independent database (General Register Office (Scotland)) was used to validate dates of death. The observed deaths per 100 000 of the population were then calculated for each group (gender, age and fracture type) at various time intervals up to eight years. A second database (Interim Life Tables for Scotland, Scottish Government) was then used to create standardised mortality ratios. Analysis showed that mortality in patients aged > 85 years with a fracture of the hip tended to return to the level of the background population between two and five years after the fracture. In those patients aged < 85 years excess mortality associated with hip fracture persisted beyond eight years. Extracapsular hip fractures and male gender also conferred increased risk.

We have investigated how medical postponement, the time to surgery and the correction of medical abnormalities, according to McLaughlin criteria, before operation affected peri-operative mortality after fracture of the hip. From February to December 2007, in addition to core data, the Scottish Hip Fracture Audit collected information relating to surgical delay. Data were available for 4284 patients which allowed 30-day survival analysis to be performed. Multivariable logistic regression models were used to control for differences in case-mix.

Patients with major clinical abnormalities were more likely to have a postponement and had a lower unadjusted 30-day survival. The time to operation and postponement were not associated with higher mortality after adjustment for case-mix. Correction of major clinical abnormalities before surgery improved the adjusted survival, but this improvement was not significant (p = 0.10). Postponement without correction of a medical abnormality before surgery was associated with a significantly lower (p = 0.006) 30-day adjusted survival. The possible benefits of postponement need to be weighed against prolonged discomfort for the patient and the possibility of the development of other complications.

Nonunion of the tibia associated with bone loss, previous infection, obliteration of the intramedullary canal or located in the distal metaphysis poses a challenge to the surgeon and significant morbidity to patients. We retrospectively reviewed the records of 24 patients who were treated by central bone grafting and compared them to those of 20 who were treated with a traditional posterolateral graft. Central bone grafting entails a lateral approach, anterior to the fibula and interosseous membrane which is used to create a central space filled with cancellous iliac crest autograft. Upon consolidation, a tibiofibular synostosis is formed that is strong enough for weight-bearing. This procedure has advantages over other methods of treatment for selected nonunions.

Of the 24 patients with central bone grafting, 23 went on to radiographic and clinical union without further intervention. All healed within a mean of 20 weeks (10 to 48). No further bone grafts were required, and few complications were encountered. These results were comparable to those of the 20 patients who underwent posterolateral bone grafting who united at a mean of 31.3 weeks (16 to 60) but one of whom required below-knee amputation for intractable sepsis.

Central bone grafting is a safe and effective treatment for difficult nonunions of the tibia.

We investigated the relationship between a number of patient and management variables and mortality after surgery for fracture of the hip. Data relating to 18 817 patients were obtained from the Scottish Hip Fracture Audit database. We divided variables into two categories, depending on whether they were case-mix (age; gender; fracture type; pre-fracture residence; pre-fracture mobility and ASA scores) or management variables (time from fracture to surgery; time from admission to surgery; grade of surgical and anaesthetic staff undertaking the procedure and anaesthetic technique).

Multivariate logistic regression analysis showed that all case-mix variables were strongly associated with post-operative mortality, even when controlling for the effects of the remaining variables. Inclusion of the management variables into the case-mix base regression model provided no significant improvement to the model. Patient case-mix variables have the most significant effect on post-operative mortality and unfortunately such variables cannot be modified by pre-operative medical interventions.

We report gender differences in the epidemiology and outcome after hip fracture from the Scottish Hip Fracture Audit, with data on admission and at 120 days follow-up from 22 orthopaedic units across the country between 1998 and 2005. Outcome measures included early mortality, length of hospital stay, 120-day residence and mobility. A multivariate logistic regression model compared outcomes between genders. The study comprised 25 649 patients of whom 5674 (22%) were men and 19 975 (78%) were women. The men were in poorer pre-operative health, despite being younger at presentation (mean 77 years (60 to 101) vs 81 years (50 to 106)). Pre-fracture residence and mobility were similar between genders.

Multivariate analysis indicated that the men were less likely to return to their home or mobilise independently at the 120-day follow-up. Mortality at 30 and 120 days was higher for men, even after differences in case-mix variables between genders were considered.

We studied the outcome and functional status of 33 patients with 34 severe open tibial fractures (Gustilo grade IIIb and IIIc). The treatment regime consisted of radical debridement, immediate bony stabilisation and early soft-tissue cover using a muscle flap (free or rotational). The review included standardised assessments of health-related quality of life (SF-36 and Euroqol) and measurement of the following parameters: gait, the use of walking aids, limb-length discrepancy, knee and ankle joint function, muscle wasting and the cosmetic appearance of the limb. Personal comments and overall patient satisfaction were also recorded. The mean follow-up was 46 months (15 to 80).

There were 30 Gustilo grade IIIb fractures and and four grade IIIc fractures. Of the 33 patients, 29 had primary internal fixation and four, external fixation; 11 (34%) later required further surgery to achieve union and two needed bone transport procedures to reconstruct large segmental defects. The mean time to union was 41 weeks (12 to 104). Two patients (6.1%) developed deep infection; both resolved with treatment.

The mean SF-36 physical and mental scores were 49 and 62 respectively. The mean state of health score for the Euroqol was 68. Patients with isolated tibial fractures had a better outcome than those with other associated injuries on both scoring systems. Knee stiffness was noted in seven patients (21%) and ankle stiffness in 19 (56%); 12 patients (41%) returned to work. Our results compare favourably with previous outcome measurements published for both limb salvage and amputation. All patients were pleased to have retained their limbs.

Various techniques have been used for the fixation of the posterior pelvis, each with disadvantages specific to the technique. In this study, a new protocol involving the placement of posterior pelvic screws in the CT suite is described and evaluated.

A total of 66 patients with unstable pelvic ring injuries was stabilised under local anaesthesia with sedation. The mean length of time for the procedure was 26 minutes per screw. There were no technical difficulties or misplaced screws and no cases of infection or nonunion. All patients stated that they would choose to have the CT scan procedure again rather than a procedure requiring general anaesthesia. The charges for the procedure were approximately £1840 ($2800) per operation. CT-guided placement of iliosacral screws is a safe, feasible, and cost-effective alternative to radiologically-guided placement in the operating theatre in selected patients.

We have carried out a prospective, randomised trial to measure the rise of temperature during reaming of the tibia before intramedullary nailing. We studied 34 patients with a mean age of 35.1 years (18 to 63) and mean injury severity score of 10 (9 to 13). The patients were randomised into two groups: group 1 included 18 patients whose procedure was undertaken without a tourniquet and group 2, 16 patients in whom a tourniquet was used. The temperature in the bone was measured directly by two thermocouples inserted into the cortical bone near the isthmus of the tibial diaphysis. Reaming was carried out to at least 1.5 mm above the required diameter of the nail. Blood loss was assessed by recording the preoperative and postoperative haemoglobin (Hb) level.

The minimum clinical follow-up was six months. In group 1 (no tourniquet), the mean Hb dropped 2.8 g/dl from 14.3 ± 1.02 g/dl to 11.5 ± 1.04 g/dl (p = 0.0001), whereas with the tourniquet, the mean decrease was 1.3 g/dl from 14 ± 1 g/dl to 12.7 ± 1.3 g/dl (p = 0.007). This difference was not statistically significant. The mean initial tibial temperature was 35.6°C (sd 0.6) and rose with reaming to levels between 36.3°C and 51.6°C. The highest temperatures were obtained with the largest reamers (11 and 12 mm, p = 0.0001) and the most rapid rise with the smallest diameters of medullary canal (8 or 9 mm). The rise of temperature was transient (20s).

We were unable to identify any effect of the use of a tourniquet on the temperature achieved. Reamed intramedullary tibial nailing induces a transient elevation of temperature which is directly related to the amount of reaming.

We performed a retrospective review of the case notes of 84 consecutive patients who had suffered a severe (Gustilo IIIb or IIIc) open fracture of the tibia after blunt trauma between 1990 and 1998. All had been treated by a radical protocol which included early soft-tissue cover with a muscle flap by a combined orthopaedic and plastic surgery service. Our ideal management is a radical debridement of the wound outside the zone of injury, skeletal stabilisation and early soft-tissue cover with a vascularised muscle flap. All patients were followed clinically and radiologically to union or for one year.

After exclusion of four patients (one unrelated death and three patients lost to follow-up), we reviewed 80 patients with 84 fractures. There were 67 men and 13 women with a mean age of 37 years (3 to 89). Five injuries were grade IIIc and 79 grade IIIb; 12 were site 41, 43 were site 42 and 29 were site 43. Debridement and stabilisation of the fracture were invariably performed immediately. In 33 cases the soft-tissue reconstruction was also completed in a single stage, while in a further 30 it was achieved within 72 hours. In the remaining 21 there was a delay beyond 72 hours, often for critical reasons unrelated to the limb injury. All grade-IIIc injuries underwent immediate vascular reconstruction, with an immediate cover by a flap in two. All were salvaged. There were four amputations, one early, one mid-term and two late, giving a final rate of limb salvage of 95%. Overall, nine pedicled and 75 free muscle flaps were used; the rate of flap failure was 3.5%. Stabilisation of the fracture was achieved with 19 external and 65 internal fixation devices (nails or plates). Three patients had significant segmental defects and required bone-transport procedures to achieve bony union. Of the rest, 51 fractures (66%) progressed to primary bony union while 26 (34%) required a bone-stimulating procedure to achieve this outcome. Overall, there was a rate of superficial infection of the skin graft of 6%, of deep infection at the site of the fracture of 9.5%, and of serious pin-track infection of 37% in the external fixator group. At final review all patients were walking freely on united fractures with no evidence of infection.

The treatment of these very severe injuries by an aggressive combined orthopaedic and plastic surgical approach provides good results; immediate internal fixation and healthy soft-tissue cover with a muscle flap is safe. Indeed, delay in cover (> 72 hours) was associated with most of the problems. External fixation was associated with practical difficulties for the plastic surgeons, a number of chronic pin-track infections and our only cases of malunion. We prefer to use internal fixation. We recommend primary referral to a specialist centre whenever possible. If local factors prevent this we suggest that after discussion with the relevant centre, initial debridement and bridging external fixation, followed by transfer, is the safest procedure.

We assessed factors which may affect union in 32 patients with nonunion of a fracture of the diaphysis of the femur and 67 comparable patients whose fracture had united. These included gender, age, smoking habit, the use of non-steroidal anti-inflammatory drugs (NSAIDs) the type of fracture (AO classification), soft-tissue injury (open or closed), the type of nail, the mode of locking, reaming v non-reaming, infection, failure of the implant, distraction at the fracture site, and the time to full weight-bearing. Patients with severe head injuries were excluded. Both groups were comparable with regard to gender, Injury Severity Score and soft-tissue injury.

There was no relationship between the rate of union and the type of implant, mode of locking, reaming, distraction or smoking. There were fewer cases of nonunion in more comminuted fractures (type C) and in patients who were able to bear weight early. There was a marked association between nonunion and the use of NSAIDs after injury (p = 0.000001) and delayed healing was noted in patients who took NSAIDs and whose fractures had united.