A systematic search of the literature published between January 1985 and February 2006 identified 62 studies which reported the results of arthroscopic procedures for chronic anterior shoulder instability or comparisons between arthroscopic and open surgery. These studies were classified by surgical technique and research methodology, and when appropriate, were included in a meta-analysis. The failure rate of arthroscopic shoulder stabilisation using staples or transglenoid suture techniques appeared to be significantly higher than that of either open surgery or arthroscopic stabilisation using suture anchors or bio-absorbable tacks. Arthroscopic anterior stabilisation using the most effective techniques has a similar rate of failure to open stabilisation after two years

Aims. Joint registries classify all further arthroplasty procedures to a knee with an existing partial arthroplasty as revision surgery, regardless of the actual procedure performed. Relatively minor procedures, including bearing exchanges, are classified in the same way as major operations requiring augments and stems. A new classification system is proposed to acknowledge and describe the detail of these procedures, which has implications for risk, recovery, and health economics. Methods. Classification categories were proposed by a surgical consensus group, then ranked by patients, according to perceived invasiveness and implications for recovery. In round one, 26 revision cases were classified by the consensus group. Results were tested for inter-rater reliability. In round two, four additional cases were added for clarity. Round three repeated the survey one month later, subject to inter- and intrarater reliability testing. In round four, five additional expert partial knee arthroplasty surgeons were asked to classify the 30 cases according to the proposed revision partial knee classification (RPKC) system. Results. Four classes were proposed: PR1, where no bone-implant interfaces are affected; PR2, where surgery does not include conversion to total knee arthroplasty, for example, a second partial arthroplasty to a native compartment; PR3, when a standard primary total knee prosthesis is used; and PR4 when revision components are necessary. Round one resulted in 92% inter-rater agreement (Kendall’s W 0.97; p < 0.005), rising to 93% in round two (Kendall’s W 0.98; p < 0.001). Round three demonstrated 97% agreement (Kendall’s W 0.98; p < 0.001), with high intra-rater reliability (interclass correlation coefficient (ICC) 0.99; 95% confidence interval 0.98 to 0.99). Round four resulted in 80% agreement (Kendall’s W 0.92; p < 0.001). Conclusion. The RPKC system accounts for all procedures which may be appropriate following partial knee arthroplasty. It has been shown to be reliable, repeatable and pragmatic. The implications for patient care and health economics are discussed. Cite this article: Bone Jt Open 2021;2(8):638–645

Aims

To evaluate if, for orthopaedic trainees, additional cadaveric simulation training or standard training alone yields superior radiological and clinical outcomes in patients undergoing dynamic hip screw (DHS) fixation or hemiarthroplasty for hip fracture.

Introduction. There is widespread variation in the management of rare orthopaedic disease, in a large part owing to uncertainty. No individual surgeon or hospital is typically equipped to amass sufficient numbers of cases to draw robust conclusions from the information available to them. The programme of research will establish the British Orthopaedic Surgery Surveillance (BOSS) Study; a nationwide reporting structure for rare disease in orthopaedic surgery. Methods. The BOSS Study is a series of nationwide observational cohort studies of pre-specified orthopaedic disease. All relevant hospitals treating the disease are invited to contribute anonymised case details. Data will be collected digitally through REDCap, with an additional bespoke software solution used to regularly confirm case ascertainment, prompt follow-up reminders and identify potential missing cases from external sources of information (i.e. national administrative data). With their consent, patients will be invited to enrich the data collected by supplementing anonymised case data with patient reported outcomes. The study will primarily seek to calculate the incidence of the rare diseases under investigation, with 95% confidence intervals. Descriptive statistics will be used to describe the case mix, treatment variations and outcomes. Inferential statistical analysis may be used to analyze associations between presentation factors and outcomes. Types of analyses will be contingent on the disease under investigation. Discussion. This study builds upon other national rare disease supporting structures, particularly those in obstetrics and paediatric surgery. It is particularly focused on addressing the evidence base for quality and safety of surgery, and the design is influenced by the specifications of the IDEAL collaboration for the development of surgical research

Aims. To identify the prevalence of neuropathic pain after lower limb fracture surgery, assess associations with pain severity, quality of life and disability, and determine baseline predictors of chronic neuropathic pain at three and at six months post-injury. Methods. Secondary analysis of a UK multicentre randomized controlled trial (Wound Healing in Surgery for Trauma; WHiST) dataset including adults aged 16 years or over following surgery for lower limb major trauma. The trial recruited 1,547 participants from 24 trauma centres. Neuropathic pain was measured at three and six months using the Doleur Neuropathique Questionnaire (DN4); 701 participants provided a DN4 score at three months and 781 at six months. Overall, 933 participants provided DN4 for at least one time point. Physical disability (Disability Rating Index (DRI) 0 to 100) and health-related quality-of-life (EuroQol five-dimension five-level; EQ-5D-5L) were measured. Candidate predictors of neuropathic pain included sex, age, BMI, injury mechanism, concurrent injury, diabetes, smoking, alcohol, analgaesia use pre-injury, index surgery location, fixation type, Injury Severity Score, open injury, and wound care. Results. The median age of the participants was 51 years (interquartile range 35 to 64). At three and six months post-injury respectively, 32% (222/702) and 30% (234/787) had neuropathic pain, 56% (396/702) and 53% (413/787) had chronic pain without neuropathic characteristics, and the remainder were pain-free. Pain severity was higher among those with neuropathic pain. Linear regression analyses found that those with neuropathic pain at six months post-injury had more physical disability (DRI adjusted mean difference 11.49 (95% confidence interval (CI) 7.84 to 15.14; p < 0.001) and poorer quality of life (EQ-5D utility -0.15 (95% CI -0.19 to -0.11); p < 0.001) compared to those without neuropathic characteristics. Logistic regression identified that prognostic factors of younger age, current smoker, below knee fracture, concurrent injuries, and regular analgaesia pre-injury were associated with higher odds of post-injury neuropathic pain. Conclusion. Pain with neuropathic characteristics is common after lower limb fracture surgery and persists to six months post-injury. Persistent neuropathic pain is associated with substantially poorer recovery. Further attention to identify neuropathic pain post-lower limb injury, predicting patients at risk, and targeting interventions, is indicated. Cite this article: Bone Joint J 2021;103-B(6):1047–1054

Aims. The aim of this study was to investigate the hypothesis that a single dose of tranexamic acid (TXA) would reduce blood loss and transfusion rates in elderly patients undergoing surgery for a subcapital or intertrochanteric (IT) fracture of the hip. Methods. In this single-centre, randomized controlled trial, elderly patients undergoing surgery for a hip fracture, either hemiarthroplasty for a subcapital fracture or intramedullary nailing for an IT fracture, were screened for inclusion. Patients were randomly allocated to a study group using a sealed envelope. The TXA group consisted of 77 patients, (35 with a subcapital fracture and 42 with an IT fracture), and the control group consisted of 88 patients (29 with a subcapital fracture and 59 with an IT fracture). One dose of 15 mg/kg of intravenous (IV) TXA diluted in 100 ml normal saline (NS,) or one dose of IV placebo 100 ml NS were administered before the incision was made. The haemoglobin (Hb) concentration was measured before surgery and daily until the fourth postoperative day. The primary outcomes were the total blood loss and the rate of transfusion from the time of surgery to the fourth postoperative day. Results. Homogeneity with respect to baseline characteristics was ensured between groups. The mean total blood loss was significantly lower in patients who received TXA (902.4 ml (-279.9 to 2,156.9) vs 1,226.3 ml (-269.7 to 3,429.7); p = 0.003), while the likelihood of requiring a transfusion of at least one unit of red blood cells was reduced by 22%. Subgroup analysis showed that these differences were larger in patients who had an IT fracture compared with those who had a subcapital fracture. Conclusion. Elderly patients who undergo intramedullary nailing for an IT fracture can benefit from a single dose of 15 mg/kg TXA before the onset of surgery. A similar tendency was identified in patients undergoing hemiarthroplasty for a subcapital fracture but not to a statistically significant level. Cite this article: Bone Joint J 2021;103-B(3):442–448

With the identification of literature shortfalls on the techniques employed in intraoperative navigated (ION) spinal surgery, we outline a number of measures which have been synthesised into a coherent operative technique. These include positioning, dissection, management of the reference frame, the grip, the angle of attack, the drill, the template, the pedicle screw, the wire, and navigated intrathecal analgesia. Optimizing techniques to improve accuracy allow an overall reduction of the repetition of the surgical steps with its associated productivity benefits including time, cost, radiation, and safety. Cite this article: Bone Joint J 2020;102-B(3):371–375

Aims. The aim of this study was to explore whether time to surgery affects functional outcome in displaced proximal humeral fractures. Methods. A total of 250 patients presenting within three weeks of sustaining a displaced proximal humeral fracture involving the surgical neck were recruited at 32 acute NHS hospitals in the United Kingdom between September 2008 and April 2011. Of the 125 participants, 109 received surgery (fracture fixation or humeral head replacement) as per randomization. Data were included for 101 and 67 participants at six-month and five-year follow-up, respectively. Oxford Shoulder Scores (OSS) collected at six, 12, and 24 months and at three, four, and five years following randomization was plotted against time to surgery. Long-term recovery was explored by plotting six-month scores against five-year scores and agreement was illustrated with a Bland-Altman plot. Results. The mean time from initial trauma to surgery was 10.5 days (1 to 33). Earlier surgical intervention did not improve OSS throughout follow-up, nor when stratified by participant age (< 65 years vs ≥ 65 years) and fracture severity (one- and two-part vs three- and four-part fractures). Participants managed later than reported international averages (three days in the United States and Germany, eight days in the United Kingdom) did not have worse outcomes. At five-year follow-up, 50 participants (76%) had the same or improved OSS compared with six months (six-month mean OSS 35.8 (SD 10.0); five-year mean OSS 40.1 (SD 9.1); r = 0.613). A Bland-Altman plot demonstrated a positive mean difference (3.3 OSS points (SD 7.92)) with wide 95% limits of agreement (-12.2 and 18.8 points). Conclusion. Timing of surgery did not affect OSS at any stage of follow-up, irrespective of age or fracture type. Most participants had maximum functional outcome at six months that was maintained at five years. These findings may help guide providers of trauma services on surgical prioritization. Cite this article: Bone Joint J 2020;102-B(1):33–41

Aims. COVID-19 has changed the practice of orthopaedics across the globe. The medical workforce has dealt with this outbreak with varying strategies and adaptations, which are relevant to its field and to the region. As one of the ‘hotspots’ in the UK , the surgical branch of trauma and orthopaedics need strategies to adapt to the ever-changing landscape of COVID-19. Methods. Adapting to the crisis locally involved five operational elements: 1) triaging and workflow of orthopaedic patients; 2) operation theatre feasibility and functioning; 3) conservation of human resources and management of workforce in the department; 4) speciality training and progression; and 5) developing an exit strategy to resume elective work. Two hospitals under our trust were redesignated based on the treatment of COVID-19 patients. Registrar/consultant led telehealth reviews were carried out for early postoperative patients. Workflows for the management of outpatient care and inpatient care were created. We looked into the development of a dedicated operating space to perform the emergency orthopaedic surgeries without symptoms of COVID-19. Between March 23 and April 23, 2020, we have surgically treated 133 patients across both our hospitals in our trust. This mainly included hip fractures and fractures/infection affecting the hand. Conclusion. The COVID-19 pandemic is not the first disease outbreak affecting the UK, nor will it be the last. The current crisis has necessitated rapid development of new hospital guidelines and early adaptive strategies in our services. Protocols and directives need to be formalized keeping in mind that COVID-19 will have a long and protracted course until a definitive cure is discovered

The COVID-19 pandemic creates unique challenges in the practice of spinal surgery. We aim to show how the use of a high-definition 3D digital exoscope can help streamline workflows, and protect both patients and healthcare staff

Aims. The direct posterior approach with subperiosteal dissection of the paraspinal muscles from the vertebrae is considered to be the standard approach for the surgical treatment of adolescent idiopathic scoliosis (AIS). We investigated whether or not a minimally-invasive surgery (MIS) technique could offer improved results. Methods. Consecutive AIS patients treated with an MIS technique at two tertiary centres from June 2013 to March 2016 were retrospectively included. Preoperative patient deformity characteristics, perioperative parameters, power of deformity correction, and complications were studied. A total of 93 patients were included. The outcome of the first 25 patients and the latter 68 were compared as part of our safety analysis to examine the effect of the learning curve. Results. In the first 25 cases, with a mean follow-up of 5.6 years (standard deviation (SD) 0.4), the mean preoperative major Cobb angle was 57.6° (SD 9.8°) and significantly corrected to mean 15.4° (SD 5.6°, 73% curve correction). The mean preoperative T5-T12 was 26.2 (SD 12.8) and significantly increased to mean 32.9 (SD 8.3). Both frontal and sagittal plane correction was conserved two years after surgery. The rate of perioperative complications was 12% and three further complications occurred (three deep delayed infection). In the latter cases, 68 patients were included with a mean follow-up time of three years (SD 0.6). The mean preoperative major Cobb angle was 58.4° (SD 9.2°) and significantly corrected to mean 20.4° (SD 7.3°).The mean preoperative T5-T12 kyphosis was 26.6° (SD 12.8°) and was significantly increased to mean 31.4° (SD 8.3°). Both frontal and sagittal correction was conserved two years after surgery. The perioperative (30 day) complication rate was 1.4%. Two (2.9%) additional complications occurred in two patients. Conclusion. MIS for AIS is associated with a significant correction of spine deformity in the frontal and sagittal planes, together with low estimated blood loss and short length of stay. The perioperative complication rate seems to be lower compared with the standard open technique based on the literature data. The longer-term safety of MIS for AIS needs to be documented with a larger cohort and compared with the standard posterior approach. Cite this article: Bone Joint J 2020;102-B(4):506–512

Artificial intelligence and machine-learning analytics have gained extensive popularity in recent years due to their clinically relevant applications. A wide range of proof-of-concept studies have demonstrated the ability of these analyses to personalize risk prediction, detect implant specifics from imaging, and monitor and assess patient movement and recovery. Though these applications are exciting and could potentially influence practice, it is imperative to understand when these analyses are indicated and where the data are derived from, prior to investing resources and confidence into the results and conclusions. In this article, we review the current benefits and potential limitations of machine-learning for the orthopaedic surgeon with a specific emphasis on data quality.

Aims. To develop a core outcome set of measurements from postoperative radiographs that can be used to assess technical skill in performing dynamic hip screw (DHS) and hemiarthroplasty, and to validate these against Van der Vleuten’s criteria for effective assessment. Methods. A Delphi exercise was undertaken at a regional major trauma centre to identify candidate measurement items. The feasibility of taking these measurements was tested by two of the authors (HKJ, GTRP). Validity and reliability were examined using the radiographs of operations performed by orthopaedic resident participants (n = 28) of a multicentre randomized controlled educational trial (ISRCTN20431944). Trainees were divided into novice and intermediate groups, defined as having performed < ten or ≥ ten cases each for DHS and hemiarthroplasty at baseline. The procedure-based assessment (PBA) global rating score was assumed as the gold standard assessment for the purposes of concurrent validity. Intra- and inter-rater reliability testing were performed on a random subset of 25 cases. Results. In total, 327 DHS and 248 hemiarthroplasty procedures were performed by 28 postgraduate year (PGY) 3 to 5 orthopaedic trainees during the 2014 to 2015 surgical training year at nine NHS hospitals in the West Midlands, UK. Overall, 109 PBAs were completed for DHS and 80 for hemiarthroplasty. Expert consensus identified four ‘final product analysis’ (FPA) radiological parameters of technical success for DHS: tip-apex distance (TAD); lag screw position in the femoral head; flushness of the plate against the lateral femoral cortex; and eight-cortex hold of the plate screws. Three parameters were identified for hemiarthroplasty: leg length discrepancy; femoral stem alignment; and femoral offset. Face validity, content validity, and feasibility were excellent. For all measurements, performance was better in the intermediate compared with the novice group, and this was statistically significant for TAD (p < 0.001) and femoral stem alignment (p = 0.023). Concurrent validity was poor when measured against global PBA score. This may be explained by the fact that they are measuring difference facets of competence. Intra-and inter-rater reliability were excellent for TAD, moderate for lag screw position (DHS), and moderate for leg length discrepancy (hemiarthroplasty). Use of a large multicentre dataset suggests good generalizability of the results to other settings. Assessment using FPA was time- and cost-effective compared with PBA. Conclusion. Final product analysis using post-implantation radiographs to measure technical skill in hip fracture surgery is feasible, valid, reliable, and cost-effective. It can complement traditional workplace-based assessment for measuring performance in the real-world operating room . It may have particular utility in competency-based training frameworks and for assessing skill transfer from the simulated to live operating theatre. Cite this article: Bone Joint Open 2020;1-9:594–604

We have reviewed 80 children who were involved in the Medical Research Council (UK) trial of surgical treatment for tuberculosis of the spine in Hong Kong. Radical surgery or debridement had been performed at mean ages of 7.6 years (n = 47) and 5.1 years (n = 33) respectively. The patients were followed up to skeletal maturity (mean 17 years). Spinal deformity was measured on lateral radiographs taken preoperatively, at six months, one year, five years and at final follow-up. Radical surgery and grafting produced a reduction in kyphos and deformity angles at six months; this correction was maintained during the growth period. By contrast, after debridement surgery there was an increase in deformity at six months, with a tendency to some spontaneous correction during the growth period. There were statistically significant differences between angles for the radical and debridement groups only at six months postoperatively, but the changes during later follow-up were similar in the radical and debridement groups. Our findings highlight the importance of the surgical correction of deformity, and provide no evidence to suggest that disproportionate posterior spinal growth contributes to progression of deformity after anterior spinal fusion in children

Aims. COVID-19 represents one of the greatest global healthcare challenges in a generation. Orthopaedic departments within the UK have shifted care to manage trauma in ways that minimize exposure to COVID-19. As the incidence of COVID-19 decreases, we explore the impact and risk factors of COVID-19 on patient outcomes within our department. Methods. We retrospectively included all patients who underwent a trauma or urgent orthopaedic procedure from 23 March to 23 April 2020. Electronic records were reviewed for COVID-19 swab results and mortality, and patients were screened by telephone a minimum 14 days postoperatively for symptoms of COVID-19. Results. A total of 214 patients had orthopaedic surgical procedures, with 166 included for analysis. Patients undergoing procedures under general or spinal anaesthesia had a higher risk of contracting perioperative COVID-19 compared to regional/local anaesthesia (p = 0.0058 and p = 0.0007, respectively). In all, 15 patients (9%) had a perioperative diagnosis of COVID-19, 14 of whom had fragility fractures; six died within 30 days of their procedure (40%, 30-day mortality). For proximal femoral fractures, our 30-day mortality was 18.2%, compared to 7% in 2019. Conclusion. Based on our findings, patients undergoing procedures under regional or local anaesthesia have minimal risk of developing COVID-19 perioperatively. Those with multiple comorbidities and fragility fractures have a higher morbidity and mortality if they contract COVID-19 perioperatively; therefore, protective care pathways could go some way to mitigate the risk. Our 30-day mortality of proximal femoral fractures was 18.2% during the COVID-19 pandemic in comparison to the annual national average of 6.1% in 2018 and the University Hospital Coventry average of 7% for the same period in 2019, as reported in the National Hip Fracture Database. Patients undergoing procedures under general or spinal anaesthesia at the peak of the pandemic had a higher risk of contracting perioperative COVID-19 compared to regional block or local anaesthesia. We question whether young patients undergoing day-case procedures under regional block or local anaesthesia with minimal comorbidities require fourteen days self-isolation; instead, we advocate that compliance with personal protective equipment, a negative COVID-19 swab three days prior to surgery, and screening questionnaire may be sufficient. Cite this article: Bone Joint Open 2020;1-9:520–529

Aims

The modified Glasgow Prognostic Score (mGPS) uses preoperative CRP and albumin to calculate a score from 0 to 2 (2 being associated with poor outcomes). mGPS is validated in multiple carcinomas. To date, its use in soft-tissue sarcoma (STS) is limited, with only small cohorts reporting that increased mGPS scores correlates with decreased survival in STS patients.

Aims. We set out to determine if there is a difference in perioperative outcomes between early and delayed surgery in paediatric supracondylar humeral fractures in the absence of vascular compromise through a systematic review and meta-analysis. Materials and Methods. A literature search was performed, with search outputs screened for studies meeting the inclusion criteria. The groups of early surgery (ES) and delayed surgery (DS) were classified by study authors. The primary outcome measure was open reduction requirement. Meta-analysis was performed in the presence of sufficient study homogeneity. Individual study risk of bias was assessed using the Risk of Bias in Non-Randomised Studies – of Interventions (ROBINS-I) criteria, with the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) criteria used to evaluate outcomes independently. Results. A total of 12 studies met the inclusion criteria (1735 fractures). Pooled mean time to surgery from injury was and 10.7 hours for ES and 91.8 hours for DS. On meta-analysis there was no significant difference between ES versus DS for the outcome of open reduction requirement. There was also no significant difference for the outcomes: Iatrogenic nerve injury, pin site infection, and re-operation. The quality of evidence for all the individual outcomes was low or very low. Conclusions. There is no evidence that delaying supracondylar fracture surgery negatively influences outcomes in the absence of vascular compromise. There are, however, notable limitations to the existing available literature

Aims. Increasingly, patients with bilateral hip arthritis wish to undergo staged total hip arthroplasty (THA). With the rise in demand for arthroplasty, perioperative risk assessment and counselling is crucial for shared decision making. However, it is unknown if complications that occur after a unilateral hip arthroplasty predict complications following surgery of the contralateral hip. Patients and Methods. We used nationwide linked discharge data from the Healthcare Cost and Utilization Project between 2005 and 2014 to analyze the incidence and recurrence of complications following the first- and second-stage operations in staged bilateral total hip arthroplasty (BTHAs). Complications included perioperative medical adverse events within 30 to 60 days, and infection and mechanical complications within one year. Conditional probabilities and odds ratios (ORs) were calculated to determine whether experiencing a complication after the first stage of surgery increased the risk of developing the same complication after the second stage. Results. A total of 13 829 patients (5790 men and 8039 women) who underwent staged BTHAs were analyzed. The mean age at first operation was 62.9 years (14 to 95). For eight of the 12 outcomes evaluated, patients who experienced the outcome following the first arthroplasty had a significantly increased probability and odds of developing that same complication following the second arthroplasty, compared with those who did not experience the complication after the first surgery. This was true for digestive complications (OR 25.67, 95% confidence interval (CI) 13.86 to 46.08; p < 0.001), urinary complications (OR 6.48, 95% CI 1.7 to 20.73; p = 0.01), haematoma (OR 12.17, 95% CI 4.55 to 31.14; p < 0.001), deep vein thrombosis (OR 4.82, 95% CI 2.34 to 9.65; p < 0.001), pulmonary embolism (OR 12.03, 95% CI 2.02 to 46.77; p = 0.01), deep hip infection (OR 534.21, 95% CI 314.96 to 909.25; p < 0.001), superficial hip infection (OR 1574.99, 95% CI 269.83 to 9291.81; p < 0.001), and mechanical malfunction (OR 117.49, 95% CI 91.55 to 150.34; p < 0.001). Conclusion. The occurrence of certain complications after unilateral THA is associated with an increased risk of the same complication occurring after staged arthroplasty of the contralateral hip. Patients who experience these complications after unilateral hip arthroplasty should be appropriately counselled regarding their risk profile prior to undergoing staged contralateral hip arthroplasty. Cite this article: Bone Joint J 2019;101-B(6 Supple B):77–83

Aims. Whether to perform hybrid surgery (HS) in contrast to anterior cervical discectomy and fusion (ACDF) when treating patients with multilevel cervical disc degeneration remains a controversial subject. To resolve this we have undertaken a meta-analysis comparing the outcomes from HS with ACDF in this condition. Methods. Seven databases were searched for studies of HS and ACDF from inception of the study to 1 September 2019. Both random-effects and fixed-effects models were used to evaluate the overall effect of the C2-C7 range of motion (ROM), ROM of superior/inferior adjacent levels, adjacent segment degeneration (ASD), heterotopic ossification (HO), complications, neck disability index (NDI) score, visual analogue scale (VAS) score, Japanese Orthopaedic Association (JOA) score, Odom’s criteria, blood loss, and operating and hospitalization time. To obtain more credible results contour-enhanced funnel plots, Egger’s and Begg’s tests, meta-regression, and sensitivity analyses were performed. Results. In total, 17 studies involving 861 patients were included in the analysis. HS was found to be superior to ACDF in maintaining C2-C7 ROM and ROM of superior/inferior adjacent levels, but HS did not reduce the incidence of associated level ASD. Also, HS did not cause a higher rate of HO than ACDF. The frequency of complications was similar between the two techniques. HS failed to achieve more favourable outcomes than ACDF using the NDI, VAS, JOA, and Odom’s scores. HS did not show any more advantages in operating or hospitalization time but did show reduction in blood loss. Conclusion. Although HS maintained cervical kinetics, it failed to reduce the incidence of ASD. This finding differs from previous reports. Moreover, patients did not show more benefits from HS with respect to symptom improvement, prevention of complications, and clinical outcomes. Cite this article: Bone Joint J 2020;102-B(8):981–996