This study was performed to determine whether pure cancellous bone graft and Kirschner (K-) wire fixation were sufficient to achieve bony union and restore alignment in scaphoid nonunion. A total of 65 patients who underwent cancellous bone graft and K-wire fixation were included in this study. The series included 61 men and four women with a mean age of 34 years (15 to 72) and mean delay to surgery of 28.7 months (3 to 240). The patients were divided into an unstable group (A) and stable group (B) depending on the pre-operative radiographs. Unstable nonunion was defined as a lateral intrascaphoid angle > 45°, or a radiolunate angle > 10°. There were 34 cases in group A and 31 cases in group B. Bony union was achieved in 30 patients (88.2%) in group A, and in 26 (83.9%) in group B (p = 0.439). Comparison of the post-operative radiographs between the two groups showed no significant differences in lateral intrascaphoid angle (p = 0.657) and scaphoid length (p = 0.670) and height (p = 0.193). The radiolunate angle was significantly different (p = 0.020) but the mean value in both groups was < 10°. Comparison of the dorsiflexion and palmar flexion of movement of the wrist and the mean Mayo wrist score at the final clinical visit in each group showed no significant difference (p = 0.190, p = 0.587 and p = 0.265, respectively). Cancellous bone graft and K-wire fixation were effective in the treatment of stable and unstable scaphoid nonunion. Cite this article: Bone Joint J 2013;95-B:809–14

Aims. The aim of this study was to investigate if there are differences in outcome between sliding hip screws (SHSs) and intramedullary nails (IMNs) with regard to fracture stability. Methods. We assessed data from 17,341 patients with trochanteric or subtrochanteric fractures treated with SHS or IMN in the Norwegian Hip Fracture Register from 2013 to 2019. Primary outcome measures were reoperations for stable fractures (AO Foundation/Orthopaedic Trauma Association (AO/OTA) type A1) and unstable fractures (AO/OTA type A2, A3, and subtrochanteric fractures). Secondary outcome measures were reoperations for A2, A3, and subtrochanteric fractures individually, one-year mortality, quality of life (EuroQol five-dimension three-level index score), pain (visual analogue scale (VAS)), and satisfaction (VAS) for stable and unstable fractures. Hazard rate ratios (HRRs) for reoperation were calculated using Cox regression analysis with adjustments for age, sex, and American Society of Anesthesiologists score. Results. Reoperation rate was lower after surgery with IMN for unstable fractures one year (HRR 0.82, 95% confidence interval (CI) 0.70 to 0.97; p = 0.022) and three years postoperatively (HRR 0.86, 95% CI 0.74 to 0.99; p = 0.036), compared with SHS. For individual fracture types, no clinically significant differences were found. Lower one-year mortality was found for IMN compared with SHS for stable fractures (HRR 0.87; 95% CI 0.78 to 0.96; p = 0.007), and unstable fractures (HRR 0.91, 95% CI 0.84 to 0.98; p = 0.014). Conclusion. This national register-based study indicates a lower reoperation rate for IMN than SHS for unstable trochanteric and subtrochanteric fractures, but not for stable fractures or individual fracture types. The choice of implant may not be decisive to the outcome of treatment for stable trochanteric fractures in terms of reoperation rate. One-year mortality rate for unstable and stable fractures was lower in patients treated with IMN. Cite this article: Bone Joint J 2022;104-B(2):274–282

Sacral fractures are often underdiagnosed, but are frequent in the setting of pelvic ring injuries. They are mostly caused by high velocity injuries or they can be pathological in aetiology. We sought to assess the clinical outcomes of the surgically treated unstable sacral fractures, with or without neurological deficits. unstable sacral fractures were included in the study. Single centre, prospectively collected data, retrospective review of patients who sustained vertically unstable fractures of the sacrum who underwent surgical fixation. out of a total of 432 patients with pelvis and acetabulum injuries. fifty six patients met the inclusion criteria. 18 patients had sustained zone one injuries. 14 patients had zone 2 injuries and 10 patients had zone 3 injurie. Operative fixation was performed percutaneously using cannulated screws in 18 patients.. Open fixation of the sacrum using the anterior approach in 6 patients. Posterior approach was indicates in all 10 of the zone 3 injuries of the sacrum. While in 4 patients, combined approaches were used. 3 patients had decompression and spinopelvic fixation. Neurological deficits were present in 16% of the patients. 2 patients presented with neurgenic bladder. Of the 4 patients who had neurological fall out, 3 resolved with posterior decompression and posterior fixation. All 4 neurological deficits were due to taction or compression of the nerve roots. No hardware failures or non unions observed. The rate of neurological deficit was related more to the degree of pelvic ring instability than to a particular fracture pattern. Low rates of complications and successful surgical treatment of sacral fractures is achiavable. Timeous accurate diagnosis mandatory

There has been a substantial increase in the surgical treatment of unstable chest wall injuries recently. While a variety of fixation methods exist, most surgeons have used plate and screw fixation. Rib-specific locking plate systems are available, however evidence supporting their use over less-expensive, conventional plate systems (such as pelvic reconstruction plates) is lacking. We sought to address this by comparing outcomes between locking plates and non-locking plates in a cohort of patients from a prior randomized trial who received surgical stabilization of their unstable chest wall injury. We used data from the surgical group of a previous multi-centred, prospective, randomized controlled trial comparing surgical fixation of acute, unstable chest wall injuries to non-operative management. In this substudy, our primary outcome was hardware-related complications and re-operation. Secondary outcomes included ventilator free days (VFDs) in the first 28 days following injury, length of ICU and hospital stay, and general health outcomes (SF-36 Physical Component Summary (PCS) and Mental Component Summary (MCS) scores). Categorical variables are reported as frequency counts and percentages and the two groups were compared using Fisher's Exact test. Continuous data are reported as median and interquartile range and the two groups were compared using the Wilcoxon rank-sum test. From the original cohort of 207 patients, 108 had been treated surgically and had data available on the type of plate construct used. Fifty-nine patients (55%) had received fixation with non-locking plates (primarily 3.5 or 2.7 mm pelvic reconstruction plates) and 49 (45%) had received fixation with locking plates (primarily rib-specific locking plates). The two groups were similar in regard to baseline and injury characteristics. In the non-locking group, 15% of patients (9/59) had evidence of hardware loosening versus 4% (2/49 patients) in the locking group (p = 0.1). The rate of re-operation for hardware complications was 3% in the non-locking group versus 0% in the locking group (p = 0.5). No patients in either group required revision fixation for loss of reduction or nonunion. There were no differences between the groups with regard to VFDs (26.3 [19.6 – 28] vs. 27.3 [18.3 – 28], p = 0.83), length of ICU stay (6.5 [2.0 – 13.1] vs 4.1 [0 – 11], p = 0.12), length of hospital stay (17 [10 – 32] vs. 17 [10 – 24], p = 0.94) or SF-36 PCS (40.9 [33.6 – 51.0] vs 43.4 [34.1 – 49.6], p = 0.93) or MCS scores (47.8 [36.9 – 57.9] vs 46.9 [40.5 – 57.4], p = 0.95). We found no statistically significant differences in outcomes between patients who received surgical stabilization of their unstable chest wall injury when comparing non-locking plates versus locking plates. However, the rate of hardware loosening was nearly 4 times higher in the non-locking plate group and trended towards statistical significance, although re-operation related to this was less frequent. This finding is not surprising, given the inherent challenges of rib fixation including thin bones, comminution, potential osteopenia and a post-operative environment of constant motion. We believe that the increased cost of locking plate fixation in this setting is likely justifiable given these findings

Aims. There are concerns regarding nail/medullary canal mismatch and initial stability after cephalomedullary nailing in unstable pertrochanteric fractures. This study aimed to investigate the effect of an additional anteroposterior blocking screw on fixation stability in unstable pertrochanteric fracture models with a nail/medullary canal mismatch after short cephalomedullary nail (CMN) fixation. Methods. Eight finite element models (FEMs), comprising four different femoral diameters, with and without blocking screws, were constructed, and unstable intertrochanteric fractures fixed with short CMNs were reproduced in all FEMs. Micromotions of distal shaft fragment related to proximal fragment, and stress concentrations at the nail construct were measured. Results. Micromotions in FEMs without a blocking screw significantly increased as nail/medullary canal mismatch increased, but were similar between FEMs with a blocking screw regardless of mismatch. Stress concentration at the nail construct was observed at the junction of the nail body and lag screw in all FEMs, and increased as nail/medullary canal mismatch increased, regardless of blocking screws. Mean stresses over regions of interest in FEMs with a blocking screw were much lower than regions of interest in those without. Mean stresses in FEMs with a blocking screw were lower than the yield strength, yet mean stresses in FEMs without blocking screws having 8 mm and 10 mm mismatch exceeded the yield strength. All mean stresses at distal locking screws were less than the yield strength. Conclusion. Using an additional anteroposterior blocking screw may be a simple and effective method to enhance fixation stability in unstable pertrochanteric fractures with a large nail/medullary canal mismatch due to osteoporosis. Cite this article: Bone Joint Res 2022;11(3):152–161

Aims. To develop an early implant instability murine model and explore the use of intermittent parathyroid hormone (iPTH) treatment for initially unstable implants. Methods. 3D-printed titanium implants were inserted into an oversized drill-hole in the tibiae of C57Bl/6 mice (n = 54). After implantation, the mice were randomly divided into three treatment groups (phosphate buffered saline (PBS)-control, iPTH, and delayed iPTH). Radiological analysis, micro-CT (µCT), and biomechanical pull-out testing were performed to assess implant loosening, bone formation, and osseointegration. Peri-implant tissue formation and cellular composition were evaluated by histology. Results. iPTH reduced radiological signs of loosening and led to an increase in peri-implant bone formation over the course of four weeks (timepoints: one week, two weeks, and four weeks). Observational histological analysis shows that iPTH prohibits the progression of fibrosis. Delaying iPTH treatment until after onset of peri-implant fibrosis still resulted in enhanced osseointegration and implant stability. Despite initial instability, iPTH increased the mean pull-out strength of the implant from 8.41 N (SD 8.15) in the PBS-control group to 21.49 N (SD 10.45) and 23.68 N (SD 8.99) in the immediate and delayed iPTH groups, respectively. Immediate and delayed iPTH increased mean peri-implant bone volume fraction (BV/TV) to 0.46 (SD 0.07) and 0.34 (SD 0.10), respectively, compared to PBS-control mean BV/TV of 0.23 (SD 0.03) (PBS-control vs immediate iPTH, p < 0.001; PBS-control vs delayed iPTH, p = 0.048; immediate iPTH vs delayed iPTH, p = 0.111). Conclusion. iPTH treatment mediated successful osseointegration and increased bone mechanical strength, despite initial implant instability. Clinically, this suggests that initially unstable implants may be osseointegrated with iPTH treatment. Cite this article: Bone Joint Res 2022;11(5):260–269

Failure of cephalomedullary fixation for proximal femur fractures is an uncommon event associated with significant morbidity to the patient and cost to the healthcare system. This institution changed nailing system from the PFNA (DePuy Synthes) to InterTan (Smith and Nephew) in February 2020. To assess for non-inferiority, a retrospective review was performed on 247 patients treated for unstable proximal femur fractures (AO 31 A2; A3). Patients were identified through manual review of fluoroscopic images. Stable fracture patterns were excluded (AO 31 A1). Pre/post operative imaging, demographic data, operative time and ASA scores assessed. Internal/external imaging and national joint registry data were reviewed for follow up. No significant difference was found in overall failure rate of PFNA vs InterTan (4.84% vs 3.23%; p = 0.748). Overall, short nails were more likely to fail by cut-out than long nails (7.5% vs 1.2%; p = 0.015). Nails which failed by varus cut-out had a higher tip/apex distance (TAD) (26.2mm vs 17.0mm; p < 0.001). Of concern, varus cut-out occurred in two InterTan nails with TAD of <25mm. The PFNA enjoyed a shorter operative time for both the short (59.1 vs 71.8 mins; p = 0.022) and long nails (98.8 vs 114.3 mins; p = 0.016) with no difference in 120-day survival rate. Overall failure rates of the PFNA and InterTan nailing systems were comparable. However, the failure rate of short nails in this study is concerning. Using long nails with a lag screw design for unstable intertrochanteric femoral fractures may reduce failure rates. Cumulative frequency analysis suggests stringent tip-apex distances of less than 21mm may reduce failure rates in lag-screw design cephulomedullary nails. This dataset suggests that unstable intertrochanteric fractures may be more reliably managed with a long cephalomedullary device

The risk of AVN is high in Unstable Slipped Capital Femoral Epiphysis (SCFE) and the optimal surgical treatment remains controversial. Our AVN rates in severe, unstable SCFE remained unchanged following the introduction of the Modified Dunn Procedure (MDP) and as a result, our practice evolved towards performing an Anterior Open Reduction and Decompression (AOR) in an attempt to potentially reduce the “second hit” phenomenon that may contribute. The aim of this study was to determine the early surgical outcomes in Unstable SCFE following AOR compared to the MDP. All moderate to severe, Loder unstable SCFEs between 2008 and 2022 undergoing either an AOR or MDP were included. AVN was defined as a non-viable post-operative SPECT-CT scan. Eighteen patients who underwent AOR and 100 who underwent MPD were included. There was no significant difference in severity (mean PSA 64 vs 66 degrees, p = 0.641), or delay to surgery (p = 0.973) between each group. There was no significant difference in the AVN rate at 27.8% compared to 24% in the AOR and MDP groups respectively (p = 0.732). The mean operative time in the AOR group was 24 minutes less, however this was not statistically significant (p = 0.084). The post-reduction PSA was 26 degrees (range, 13–39) in the AOR group and 9 degrees (range, -7 to 29) in the MDP group (p<0.001). Intra-operative femoral head monitoring had a lower positive predictive value in the AOR group (71% compared to 90%). Preliminary results suggest the AVN rate is not significantly different following AOR. There is less of an associated learning curve with the AOR, but as anticipated, a less anatomical reduction was achieved in this group. We still feel that there is a role for the MDP in unstable slips with a larger remodelling component

Aims. The best method of treating unstable pelvic fractures that involve the obturator ring is still a matter for debate. This study compared three methods of treatment: nonoperative, isolated posterior fixation and combined anteroposterior stabilization. Patients and Methods. The study used data from the German Pelvic Trauma Registry and compared patients undergoing conservative management (n = 2394), surgical treatment (n = 1345) and transpubic surgery, including posterior stabilization (n = 730) with isolated posterior osteosynthesis (n = 405) in non-complex Type B and C fractures that only involved the obturator ring anteriorly. Calculated odds ratios were adjusted for potential confounders. Outcome criteria were intraoperative and general short-term complications, the incidence of nerve injuries, and mortality. Results. Operative stabilization reduced mortality by 36% (odds ratio (OR) 0.64, 95% confidence interval (CI) 0.42 to 0.98) but the incidence of complications was twice as high (OR 2.04, 95% CI 1.57 to 2.64). Mortality and the incidence of neurological deficits at discharge were no different after isolated posterior or combined anteroposterior fixation. However, the odds of both surgical (98%, OR 1.98, 95%CI 1.22 to 3.22) and general complications (43%, OR 1.43, 95% CI 1.02 to 2.00) were higher in the group with the more extensive surgery. Conclusion. Operative stabilization is recommended for non-complex unstable pelvic fractures. The need for anterior fixation of obturator ring fractures should, however, be considered critically. Cite this article: Bone Joint J 2018;100-B:973–83

The purpose of this study was to identify changing trends in the pattern of distribution of the type and demographics of fractures of the hip in the elderly between 2001 and 2010. A retrospective cross-sectional comparison was conducted between 179 fractures of the hip treated in 2001, 357 treated in 2006 and 454 treated in 2010. Patients aged < 60 years and those with pathological and peri-prosthetic fractures were excluded. Fractures were classified as stable extracapsular, unstable extracapsular or intracapsular fractures. The mean age of the 179 patients (132 women (73.7%)) treated in 2001 was 80.8 years (60 to 96), 81.8 years (61 to 101) in the 357 patients (251 women (70.3%)) treated in 2006 and 82.0 years (61 to 102) in the 454 patients (321 women (70.1%)) treated in 2010 (p = 0.17). There was no difference in the gender distribution between the three study years (p = 0.68). The main finding was a steep rise in the proportion of unstable peritrochanteric fractures. The proportion of unstable extracapsular fractures was 32% (n = 57) in 2001, 35% (n = 125) in 2006 and 45% (n = 204) in 2010 (p < 0.001). This increase was not significant in patients aged between 60 and 69 years (p = 0.84), marginally significant in those aged between 70 and 79 years (p = 0.04) and very significant in those aged > 80 years (p < 0.001). The proportion of intracapsular fractures did not change (p = 0.94). At present, we face not only an increasing number of fractures of the hip, but more demanding and complex fractures in older patients than a decade ago. This study does not provide an explanation for this change. Cite this article: Bone Joint J 2013;95-B:1250–4

The aim of this study was to evaluate the long-term outcomes of patients who had sustained an unstable ankle fracture with a posterior malleolus fracture (PMF) and without (N-PMF). Adult patients presenting to a single academic trauma centre in Edinburgh, UK, between 2009 and 2012 with an unstable ankle fracture requiring surgery were identified. The primary outcome measure was the Olerud Molander Ankle Score (OMAS). Secondary measures included Euroqol-5D-3L Index (Eq5D3L), Euroqol-5D-VAS and Manchester Oxford Foot Questionnaire (MOXFQ). There were 304 patients in the study cohort. The mean age was 49.6 years (16.3–78.3) and 33% (n=100) male and 67% (n=204) female. Of these, 67% (n=204) had a PMF and 33% did not (n=100). No patient received a computed tomography (CT) scan pre-operatively. Only 10% of PMFs (22/204) were managed with internal fixation. At a mean of 13.8 years (11.3 – 15.3) the median OMAS score was 85 (Interquartile Range 60 – 100). There was no difference in OMAS between the N-PMF and PMF groups (85 [56.25 – 100] vs 85 [61.25 – 100]; p = 0.580). There was also no difference for MOXFQ (N-PMF 7 [0 – 36.75] vs PMF 8 [0–38.75]; p = 0.643), the EQ5D Index (N-PMF 0.8 [0.7 – 1] vs PMF 0.8 [0.7 – 1]; p = 0.720) and EQ5D VAS (N-PMF 80 [70 – 90] vs PMF 80 [60 – 90]; p = 0.224). The presence of a PMF does not affect the long-term patient reported outcomes in patients with a surgically managed unstable ankle fracture

Aims. Ankle fracture is one of the most common musculoskeletal injuries sustained in the UK. Many patients experience pain and physical impairment, with the consequences of the fracture and its management lasting for several months or even years. The broad aim of ankle fracture treatment is to maintain the alignment of the joint while the fracture heals, and to reduce the risks of problems, such as stiffness. More severe injuries to the ankle are routinely treated surgically. However, even with advances in surgery, there remains a risk of complications; for patients experiencing these, the associated loss of function and quality of life (Qol) is considerable. Non-surgical treatment is an alternative to surgery and involves applying a cast carefully shaped to the patient’s ankle to correct and maintain alignment of the joint with the key benefit being a reduction in the frequency of common complications of surgery. The main potential risk of non-surgical treatment is a loss of alignment with a consequent reduction in ankle function. This study aims to determine whether ankle function, four months after treatment, in patients with unstable ankle fractures treated with close contact casting is not worse than in those treated with surgical intervention, which is the current standard of care. Methods. This trial is a pragmatic, multicentre, randomized non-inferiority clinical trial with an embedded pilot, and with 12 months clinical follow-up and parallel economic analysis. A surveillance study using routinely collected data will be performed annually to five years post-treatment. Adult patients, aged 60 years and younger, with unstable ankle fractures will be identified in daily trauma meetings and fracture clinics and approached for recruitment prior to their treatment. Treatments will be performed in trauma units across the UK by a wide range of surgeons. Details of the surgical treatment, including how the operation is done, implant choice, and the recovery programme afterwards, will be at the discretion of the treating surgeon. The non-surgical treatment will be close-contact casting performed under anaesthetic, a technique which has gained in popularity since the publication of the Ankle Injury Management (AIM) trial. In all, 890 participants (445 per group) will be randomly allocated to surgical or non-surgical treatment. Data regarding ankle function, QoL, complications, and healthcare-related costs will be collected at eight weeks, four and 12 months, and then annually for five years following treatment. The primary outcome measure is patient-reported ankle function at four months from treatment. Anticipated impact. The 12-month results will be presented and published internationally. This is anticipated to be the only pragmatic trial reporting outcomes comparing surgical with non-surgical treatment in unstable ankle fractures in younger adults (aged 60 years and younger), and, as such, will inform the National Institute for Health and Care Excellence (NICE) ‘non-complex fracture’ recommendations at their scheduled update in 2024. A report of long-term outcomes at five years will be produced by January 2027. Cite this article: Bone Jt Open 2024;5(3):184–201

The purpose of this study was to investigate the effectiveness of casting in achieving acceptable radiological parameters for unstable ankle injuries. This retrospective observational cohort study was conducted involving the retrieval of X-rays of all ankles taken over a 2 year period in an urban setting to investigate the radiological outcomes of cast management for unstable ankle fractures using four acceptable parameters measured on a single X- ray at union. The Picture Archiving and Communication System (PACS) was used, the X-rays were measured by a single observer. From the 1st of January 2020 to the 31st of December 2021, a total of 1043 ankle fractures were treated at the three hospitals with a male to female ratio of 1:1.7. Of the 628 unstable ankle injuries, 19% of patients were lost to follow up. 190 were managed conservatively with casts, requiring an average of 4 manipulations, with a malunion rate of 23.2%. Unstable ankle injuries that were treated surgically from the outset and those who failed conservative management and subsequently converted to surgery had a malunion rate of 8.1% and 11.0% respectively. Unstable ankle fractures pose a challenge with a high rate of radiological malunion, regardless of the treatment Casting surgery from the outset or converted to surgery, with rates of 23% and 8% and 11% respectively. In this multivariate analysis we found that conservative management was the only factor influencing the incidence of malunion, age, sex and type of fracture did not have a scientific significant influence

Aims. Evaluate if treating an unstable femoral neck fracture with a locking plate and spring-loaded telescoping screw system would improve construct stability compared to gold standard treatment methods. Methods. A 31B2 Pauwels’ type III osteotomy with additional posterior wedge was cut into 30 fresh-frozen femur cadavers implanted with either: three cannulated screws in an inverted triangle configuration (CS), a sliding hip screw and anti-rotation screw (SHS), or a locking plate system with spring-loaded telescoping screws (LP). Dynamic cyclic compressive testing representative of walking with increasing weight-bearing was applied until failure was observed. Loss of fracture reduction was recorded using a high-resolution optical motion tracking system. Results. LP constructs demonstrated the highest mean values for initial stiffness and failure load. LP and SHS constructs survived on mean over 50% more cycles and to loads 450 N higher than CS. During the early stages of cyclic loading, mean varus collapse of the femoral head was 0.5° (SD 0.8°) for LP, 0.7° (SD 0.7°) for SHS, and 1.9° (SD 2.3°) for CS (p = 0.071). At 30,000 cycles (1,050 N) mean femoral neck shortening was 1.8 mm (SD 1.9) for LP, 2.0 mm (SD 0.9) for SHS, and 3.2 mm (SD 2.5) for CS (p = 0.262). Mean leg shortening at construct failure was 4.9 mm (SD 2.7) for LP, 8.9 mm (SD 3.2) for SHS, and 7.0 mm (SD 4.3) for CS (p = 0.046). Conclusion. Use of the LP system provided similar (hip screw) or better (cannulated screws) biomechanical performance as the current gold standard methods suggesting that the LP system could be a promising alternative for the treatment of unstable fractures of the femoral neck. Cite this article: Bone Joint Res 2020;9(6):314–321

Aims. Treatment of Weber B ankle fractures that are stable on weightbearing radiographs but unstable on concomitant stress tests (classified SER4a) is controversial. Recent studies indicate that these fractures should be treated nonoperatively, but no studies have compared alternative nonoperative options. This study aims to evaluate patient-reported outcomes and the safety of fracture treatment using functional orthosis versus cast immobilization. Methods. A total of 110 patients with Weber B/SER4a ankle fractures will be randomized (1:1 ratio) to receive six weeks of functional orthosis treatment or cast immobilization with a two-year follow-up. The primary outcome is patient-reported ankle function and symptoms measured by the Manchester-Oxford Foot and Ankle Questionnaire (MOxFQ); secondary outcomes include Olerud-Molander Ankle Score, radiological evaluation of ankle congruence in weightbearing and gravity stress tests, and rates of treatment-related adverse events. The Regional Committee for Medical and Health Research (approval number 277693) has granted ethical approval, and the study is funded by South-Eastern Norway Regional Health Authority (grant number 2023014). Discussion. Randomized controlled trials are needed to evaluate alternative nonoperative treatment options for Weber B/SER4a ankle fractures, as current clinical guidelines are based on biomechanical reasoning. The findings will be shared through publication in peer-reviewed journals and presentations at conferences. Cite this article: Bone Jt Open 2023;4(9):713–719

Unstable pelvic injuries in young children with an immature pelvis have different modes of failure from those in adolescents and adults. We describe the pathoanatomy of unstable pelvic injuries in these children, and the incidence of associated avulsion of the iliac apophysis and fracture of the ipsilateral fifth lumbar transverse process (L5-TP). We retrospectively reviewed the medical records of 33 children with Tile types B and C pelvic injuries admitted between 2007 and 2014; their mean age was 12.6 years (2 to 18) and 12 had an immature pelvis. Those with an immature pelvis commonly sustained symphyseal injuries anteriorly with diastasis, rather than the fractures of the pubic rami seen in adolescents. Posteriorly, transsacral fractures were more commonly encountered in mature children, whereas sacroiliac dislocations and fracture-dislocations were seen in both age groups. Avulsion of the iliac apophysis was identified in eight children, all of whom had an immature pelvis with an intact ipsilateral L5-TP. Young children with an immature pelvis are more susceptible to pubic symphysis and sacroiliac diastasis, whereas bony failures are more common in adolescents. Unstable pelvic injuries in young children are commonly associated with avulsion of the iliac apophysis, particularly with displaced SI joint dislocation and an intact ipsilateral L5-TP. Cite this article: Bone Joint J 2015; 97-B:696–704

This prospective randomised trial aimed to assess the superiority of internal fixation of well-reduced medial malleolar fractures (displacement □2mm) compared with non-fixation, following fibular stabilisation in patients undergoing surgical management of a closed unstable ankle fracture. A total of 154 adult patients with a bi- or trimalleolar fracture were recruited from a single centre. Open injuries and vertically unstable medial malleolar fractures were excluded. Following fibular stabilisation, patients were randomised intra-operatively on a 1:1 basis to fixation or non-fixation after satisfactory fluoroscopic fracture reduction was confirmed. The primary outcome was the Olerud Molander Ankle Score (OMAS) at 12 months post-randomisation. Complications were documented over the follow-up period. The baseline group demographics and injury characteristics were comparable. There were 144 patients reviewed at the primary outcome point (94%). The median OMAS was 80 (IQR, 60-90) in the fixation group vs. 72.5 (IQR, 55-90) in the non-fixation group (p=0.165). Complication rates were comparable, although significantly more patients (n=13, 20%) in the non-fixation group developed a radiographic non-union (p<0.001). The majority (n=8/13) were asymptomatic, with one patient requiring surgical reintervention. In the non-fixation group, a superior outcome was associated with an anatomical medial malleolar fracture reduction. Internal fixation is not superior to non-fixation of well-reduced medial malleolar fractures when managing unstable ankle fractures. However, one in five patients following non-fixation developed a radiographic non-union and whilst the re-intervention rate to manage this was low, the longer-term consequences of this are unknown. The results of this trial may support selective non-fixation of anatomically reduced fractures

Introduction. The incidence of dislocation after total hip arthroplasty (THA) was reported to be 0.5 to 10% in primary THA and 10 to 25 % in revision THA. The main causes of instability after THA were reported to be implant malalignment and inappropriate soft tissue tension. However, there was no study about quantitative data of soft tissue tension of unstable THA. The purpose of this study is to clarify the features of soft tissue tension of unstable THA in comparison to stable THA. Methods. The subjects were 15 patients with 15 THAs who had developed recurrent dislocation after primary THA. Thirty four patients with 37 THAs who developed no dislocation for one year after surgery were recruited as a stable THA group. In both group, all THAs were performed through posterolateral approach. In order to assess the soft tissue tension of THA, we recorded antero-posterior radiographs of the hips while applying distal traction to the leg with traction forces of 20?, 30%, 40% of body weight (BW). The distance of separation of the head and the cup after traction was measured under correction of magnification. Nine of 15 THAs in the unstable THA group and 32 of 37 THAs in the stable THA group were unilateral involvement. In the hips with unilateral involvement, the femoral offset difference between the healthy hip and the reconstructed hip were evaluated. Statistical analysis was performed with χ2 testand Mann-Whitney U test, and statistical significance was set at P<0.05. Results and Discussion. The average separation distance of the head and the cup was 5.2 ± 3.4mm (SD) at 40%BW, 4.3±3.2mm at 30%BW, and 3.2±2.8mm at 20%BW in the unstable THA group. The average separation distance of the head and the cup was 1.4±1.5mm at 40%BW, 1.1±1.4mm at 30%BW, and 0.9±1.2mm at 20%BW in the stable THA group. There were statistically significant differences in the separation distance between the groups in all ranges of traction force. The femoral offset difference between the operated side and the healthy side was −1.2±5.6mm in the unstable THA group and 3.1±4.8mm in the stable THA group. There were no significant difference in the femoral offset difference, however the femoral offset tends to be small in the unstable THA group compared to the stable THA group (P=0.05). The leg length discrepancy was −3.1±11.6mm in the unstable THA group and 2.7±7.1mm in the stable THA group. There were no significant difference in the leg length discrepancy (P=0.12). Conclusion. The separation distance of the head and the cup during leg distal traction in the unstable THA group is about four times larger than that in the stable THA group. The femoral offset tended to be smaller in the unstable THA group compared to the stable THA group

Historically avoidance of avascular necrosis (AVN) has been the primary objective in the management of an acute unstable slipped upper femoral epiphysis (SUFE). When achieved through pinning in situ it was invariably associated with significant malunion. With increasing appreciation of the consequences of femoroacetabular impingement, modern techniques aim to correct deformity and avoid AVN. Exactly what constitutes an acute unstable SUFE is a source of debate but should represent 5–10% of all cases. This audit reviewed cases over the past 25 years treated in one region. Of 89 patients with 113 slips, 21 hips were recorded as unstable. During this period the management has evolved from closed reduction and stabilization through pinning in situ, to open reduction. Radiographic outcomes following these three treatment methods were compared with record of any subsequent surgery in the form of osteotomy or total hip arthroplasty. Currently the lowest reported incidence of AVN in patients with an acute unstable slip is associated with the Parsch technique which combines open arthrotomy, digital reduction and screw fixation. Early outcomes with this technique are in accordance with those reported in the literature and represents a significant improvement in outcome when compared to earlier techniques used in the management of the severe unstable SUFE

Unstable chest wall injuries have high rates of mortality and morbidity. These injuries can lead to respiratory dysfunction, and are associated with high rates of pneumonia, sepsis, prolonged ICU stays, and increased health care costs. Numerous studies have demonstrated improved outcomes with surgical fixation compared to non-operative treatment. However, an adequately powered multi-centre randomized controlled study using modern fixation techniques has been lacking. We present a multi-centred, prospective, randomized controlled trial comparing surgical fixation of acute, unstable chest wall injuries with the current standard of non-operative management. Patients aged 16–85 with a flail chest (3 or more consecutive, segmental, displaced rib fractures), or severe deformity of the chest wall, were recruited from multiple trauma centers across North America. Exclusion criteria included: severe pulmonary contusion, severe head trauma, randomization>72 hours from injury, inability to perform surgical fixation within 96 hours from injury (in those randomized to surgery), fractures of the floating ribs, or fractures adjacent to the spine not amendable to surgical fixation. Patients were seen in follow-up for one year. The primary outcome was days free from mechanical ventilation in the first 28 days following injury. Secondary outcomes were days in ICU, rates of pneumonia, sepsis, need for tracheostomy, mortality, general health outcomes, pulmonary function testing, and other complications of treatment. A sample size of 206 was required to detect a difference of 2 ventilator-free days between the two groups, using a 2-tailed alpha error of 0.05 and a power of 0.80. A total of 207 patients were recruited from 15 sites across Canada and USA, from 2011–2018. Ninety-nine patients were randomized to non-operative treatment, and 108 were randomized to surgical fixation. Overall, the mean age was 53 years, and 75% of patients were male, with 25% females. The commonest mechanisms of injury were: motor vehicle collisions (34%), falls (20%), motorcycle collisions (14%), and pedestrian injuries (11%). The mean injury severity score (ISS) at admission was 26, and patients had a mean of 10 rib fractures. Eighty-nine percent of patients had pneumothorax, 76% had haemothorax, and 54% had pulmonary contusion. There were no differences between the two groups in terms of demographics. The final results will be available and presented at the COA meeting in Halifax. This is the largest randomized controlled trial to date, comparing surgical fixation to non-operative treatment of unstable chest wall and flail chest injuries. The results of this study will shed light on the best treatment options for patients with such injuries, help understand outcomes, and guide treatment. The final results will be available and presented at the COA meeting in Halifax