Aims. The aim of this retrospective study was to assess the incidence of early periprosthetic femoral fracture (PFF) associated with Charnley-Kerboull (CK) femoral components cemented according to the ‘French paradox’ principles through the Hueter anterior approach (HAA) in patients older than 70 years. Methods. From a prospectively collected database, all short CK femoral components implanted consecutively from January 2018 to May 2022 through the HAA in patients older than 70 years were included. Exclusion criteria were age below 70 years, use of cementless femoral component, and approaches other than the HAA. A total of 416 short CK prostheses used by 25 surgeons with various levels of experience were included. All patients had a minimum of one-year follow-up, with a mean of 2.6 years (SD 1.1). The mean age was 77.4 years (70 to 95) and the mean BMI was 25.3 kg/m. 2. (18.4 to 43). Femoral anatomy was classified according to Dorr. The measured parameters included canal flare index, morphological cortical index, canal-calcar ratio, ilium-ischial ratio, and anterior superior iliac spine to greater trochanter (GT) distance. Results. Among the 416 THAs, two PFFs (0.48% (95% confidence interval 0.13 to 1.74)) were observed, including one Vancouver type B2 fracture 24 days postoperatively and one intraoperative Vancouver type B1 fracture. Valgus malalignment and higher canal bone ratio were found to be associated with PFF. Conclusion. This study demonstrated that short CK femoral components cemented according to the French paradox were associated with a low rate of early PFF (0.48%) in patients aged over 70 years. Longer follow-up is warranted to further evaluate the rate of fracture that may occur during the bone remodelling process and with time. Cite this article: Bone Joint J 2024;106-B(3 Supple A):67–73

Aims. The primary aim of this study was to analyse the position of the acetabular and femoral components in total hip arthroplasty undertaken using an anterior surgical approach. . Patients and Methods. In a prospective, single centre study, we used the EOS imaging system to analyse the position of components following THA performed via the anterior approach in 102 patients (103 hips) with a mean age of 64.7 years (. sd. 12.6). Images were taken with patients in the standing position, allowing measurement of both anatomical and functional anteversion of the acetabular component. . Results. The mean inclination of the acetabular component was 39° (standard deviation (. sd). 6), the mean anatomical anteversion was 30° (. sd. 10), and the mean functional anteversion was 31° (. sd. 8) five days after surgery. The mean anteversion of the femoral component was 20° (. sd.  11). Anatomical and functional anteversion of the acetabular component differed by >  10° in 23 (22%) cases. Pelvic tilt was the only pre-operative predictive factor of this difference. Conclusion. Our study showed that anteversion of the acetabular component following THA using the anterior approach was greater than the recommended target value, and that substantial differences were observed in some patients when measured using two different measurement planes. If these results are confirmed by further studies, and considering that the anterior approach is intended to limit the incidence of dislocation, a new correlation study for each reference plane (anatomical and functional) will be necessary to define a ‘safe zone’ for use with the anterior approach. Take home message: EOS imaging system is helpful in the pre-operative and post-operative radiological analysis of total hip arthroplasty. Cite this article: Bone Joint J 2016;98-B:326–333

Aims. Lateral femoral cutaneous nerve (LFCN) injury is a complication after periacetabular osteo-tomy (PAO) using an anterior approach, which might adversely affect the outcome. However, no prospective study has assessed the incidence and severity of this injury and its effect on the clinical outcomes over a period of time for longer than one year after PAO. The aim of this study was to assess the incidence and severity of the symptoms of LFCN injury for ≥ three years after PAO and report its effect on clinical outcomes. Methods. A total of 40 hips in 40 consecutive patients who underwent PAO between May 2016 and July 2018 were included in the study, as further follow-up of the same patients from a previous study. We prospectively evaluated the incidence, severity, and area of symptoms following LFCN injury. We also recorded the clinical scores at one year and ≥ three years postoperatively using the 36-Item Short Form Health Survey (SF-36) and Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ) scores. Results. A total of 20 patients (50%) had symptoms of a LFCN injury at one year after PAO. At ≥ three years postoperatively, the symptoms had completely resolved in seven of these patients and 13 (33%) had persistent symptoms. The severity and area of symptoms did not significantly differ between one and ≥ three years postoperatively. The JHEQ showed significant differences in the patient satisfaction and mental scores between those with and those without sypmtoms of LFCN injury at ≥ three years postoperatively, while there was no significant difference in the mean SF-36 scores. Conclusion. The incidence of LFCN injury after PAO using an anterior approach is high. The outcome of PAO, ≥ three years postoperatively, is poorer in patients with persistent symptoms from a perioperative LFCN injury, in that patient satisfaction and mental health scores are adversely affected. Cite this article: Bone Joint J 2024;106-B(5 Supple B):11–16

Aims. The aim of this study was to radiologically evaluate the quality of cement mantle and alignment achieved with a polished tapered cemented femoral stem inserted through the anterior approach and compared with the posterior approach. Methods. A comparative retrospective study of 115 consecutive hybrid total hip arthroplasties or cemented hemiarthroplasties in 110 patients, performed through anterior (n = 58) or posterior approach (n = 57) using a collarless polished taper-slip femoral stem, was conducted. Cement mantle quality and thickness were assessed in both planes. Radiological outcomes were compared between groups. Results. No significant differences were identified between groups in Barrack grade on the anteroposterior (AP) (p = 0.640) or lateral views (p = 0.306), or for alignment on the AP (p = 0.603) or lateral views (p = 0.254). An adequate cement mantle (Barrack A or B) was achieved in 77.6% (anterior group, n = 45) and in 86% (posterior group, n = 49), respectively. Multivariate analysis revealed factors associated with unsatisfactory cement mantle (Barrack C or D) included higher BMI, left side, and Dorr Type C morphology. A mean cement mantle thickness of ≥ 2 mm was achieved in all Gruen zones for both approaches. The mean cement mantle was thicker in zone 7 (p < 0.001) and thinner in zone 9 for the anterior approach (p = 0.032). Incidence of cement mantle defects between groups was similar (6.9% (n = 4) vs 8.8% (n = 5), respectively; p = 0.489). Conclusion. An adequate cement mantle and good alignment can be achieved using a collarless polished tapered femoral component inserted through the anterior approach. Cite this article: Bone Joint J 2021;103-B(7 Supple B):46–52

Aims. The most effective surgical approach for total hip arthroplasty (THA) remains controversial. The direct anterior approach may be associated with a reduced risk of dislocation, faster recovery, reduced pain and fewer surgical complications. This systematic review aims to evaluate the current evidence for the use of this approach in THA. Materials and Methods. Following the Cochrane collaboration, an extensive literature search of PubMed, Medline, Embase and OvidSP was conducted. Randomised controlled trials, comparative studies, and cohort studies were included. Outcomes included the length of the incision, blood loss, operating time, length of stay, complications, and gait analysis. Results. A total of 42 studies met the inclusion criteria. Most were of medium to low quality. There was no difference between the direct anterior, anterolateral or posterior approaches with regards to length of stay and gait analysis. Papers comparing the length of the incision found similar lengths compared with the lateral approach, and conflicting results when comparing the direct anterior and posterior approaches. . Most studies found the mean operating time to be significantly longer when the direct anterior approach was used, with a steep learning curve reported by many. Many authors used validated scores including the Harris hip score, and the Western Ontario and McMaster Universities Arthritis Index. These mean scores were better following the use of the direct anterior approach for the first six weeks post-operatively. Subsequently there was no difference between these scores and those for the posterior approach. Conclusion . There is little evidence for improved kinematics or better long-term outcomes following the use of the direct anterior approach for THA. There is a steep learning curve with similar rates of complications, length of stay and outcomes. . Well-designed, multi-centre, prospective randomised controlled trials are required to provide evidence as to whether the direct anterior approach is better than the lateral or posterior approaches when undertaking THA. Cite this article: Bone JointJ 2017;99-B:732–40

Aims. Posterior column plating through the single anterior approach reduces the morbidity in acetabular fractures that require stabilization of both the columns. The aim of this study is to assess the effectiveness of posterior column plating through the anterior intrapelvic approach (AIP) in the management of acetabular fractures. Methods. We retrospectively reviewed the data from R G Kar Medical College, Kolkata, India, from June 2018 to April 2023. Overall, there were 34 acetabulum fractures involving both columns managed by medial buttress plating of posterior column. The posterior column of the acetabular fracture was fixed through the AIP approach with buttress plate on medial surface of posterior column. Mean follow-up was 25 months (13 to 58). Accuracy of reduction and effectiveness of this technique were measured by assessing the Merle d’Aubigné score and Matta’s radiological grading at one year and at latest follow-up. Results. Immediate postoperative radiological Matta’s reduction accuracy showed anatomical reduction (0 to 1 mm) in 23 cases (67.6%), satisfactory (2 to 3 mm) in nine (26.4%), and unsatisfactory (> 3 mm) in two (6%). Merle d’Aubigné score at the end of one year was calculated to be excellent in 18 cases (52.9%), good in 11 (32.3%), fair in three (8.8%), and poor in two (5.9%). Matta’s radiological grading at the end of one year was calculated to be excellent in 16 cases (47%), good in nine (26.4%), six in fair (17.6%), and three in poor (8.8%). Merle d’Aubigné score at latest follow-up deteriorated by one point in some cases, but the grading remained the same; Matta’s radiological grading at latest follow-up also remained unchanged. Conclusion. Stabilization of posterior column through AIP by medial surface plate along the sciatic notch gives good stability to posterior column, and at the same time can avoid morbidity of the additional lateral window. Cite this article: Bone Jt Open 2024;5(2):147–153

Aims. Surgical approaches that claim to be minimally invasive, such as the direct anterior approach (DAA), are reported to have a clinical advantage, but are technically challenging and may create more injury to the soft-tissues during joint exposure. Our aim was to quantify the effect of soft-tissue releases on the joint torque and femoral mobility during joint exposure for hip resurfacing performed via the DAA. Methods. Nine fresh-frozen hip joints from five pelvis to mid-tibia cadaveric specimens were approached using the DAA. A custom fixture consisting of a six-axis force/torque sensor and motion sensor was attached to tibial diaphysis to measure manually applied torques and joint angles by the surgeon. Following dislocation, the torques generated to visualize the acetabulum and proximal femur were assessed after sequential release of the joint capsule and short external rotators. Results. Following initial exposure, the ischiofemoral ligament (7 to 8 o’clock) was the largest restrictor of exposure of the acetabulum, contributing to a mean 25% of overall external rotational restraint. The ischiofemoral ligament (10 to 12 o’clock) was the largest restrictor of exposure of the proximal femur, contributing to 25% of overall extension restraint. Releasing the short external rotators had minimal contribution in torque generated during joint exposure (≤ 5%). Conclusion. Adequate exposure of both proximal femur and acetabulum may be achieved with minimal torque by performing a full proximal circumferential capsulotomy while preserving short external rotators. The joint torque generated and exposure achieved is dependent on patient factors; therefore, some cases may necessitate further releases. Cite this article: Bone Joint J 2024;106-B(3 Supple A):59–66

Aims. Excessive posterior pelvic tilt (PT) may increase the risk of anterior instability after total hip arthroplasty (THA). The aim of this study was to investigate the changes in PT occurring from the preoperative supine to postoperative standing position following THA, and identify factors associated with significant changes in PT. Methods. Supine PT was measured on preoperative CT scans and standing PT was measured on preoperative and one-year postoperative standing lateral radiographs in 933 patients who underwent primary THA. Negative values indicate posterior PT. Patients with > 13° of posterior PT from preoperative supine to postoperative standing (ΔPT ≤ -13°) radiographs, which corresponds to approximately a 10° increase in functional anteversion of the acetabular component, were compared with patients with less change (ΔPT > -13°). Logistic regression analysis was used to assess preoperative demographic and spinopelvic parameters predictive of PT changes of ≤ -13°. The area under receiver operating characteristic curve (AUC) determined the diagnostic accuracy of the predictive factors. Results. PT changed from a mean of 3.8° (SD 6.0°)) preoperatively to -3.5° (SD 6.9°) postoperatively, a mean change of -7.4 (SD 4.5°; p < 0.001). A total of 95 patients (10.2%) had ≤ -13° change in PT from preoperative supine to postoperative standing. The strongest predictive preoperative factors of large changes in PT (≤ -13°) from preoperative supine to postoperative standing were a large posterior change in PT from supine to standing, increased supine PT, and decreased standing PT (p < 0.001). Flexed-seated PT (p = 0.006) and female sex (p = 0.045) were weaker significant predictive factors. When including all predictive factors, the accuracy of the AUC prediction was 84.9%, with 83.5% sensitivity and 71.2% specificity. Conclusion. A total of 10% of patients had > 13° of posterior PT postoperatively compared with their supine pelvic position, resulting in an increased functional anteversion of > 10°. The strongest predictive factors of changes in postoperative PT were the preoperative supine-to-standing differences, the anterior supine PT, and the posterior standing PT. Surgeons who introduce the acetabular component with the patient supine using an anterior approach should be aware of the potentially large increase in functional anteversion occurring in these patients. Cite this article: Bone Joint J 2024;106-B(3 Supple A):74–80

Aims. There is evidence that morbidly obese patients have more intra- and postoperative complications and poorer outcomes when undergoing total hip arthroplasty (THA) with the direct anterior approach (DAA). The aim of this study was to determine the efficacy of DAA for THA, and compare the complications and outcomes of morbidly obese patients with nonobese patients. Methods. Morbidly obese patients (n = 86), with BMI ≥ 40 kg/m. 2. who underwent DAA THA at our institution between September 2010 and December 2017, were matched to 172 patients with BMI < 30 kg/m. 2. Data regarding demographics, set-up and operating time, blood loss, radiological assessment, Harris Hip Score (HHS), International Hip Outcome Tool (12-items), reoperation rate, and complications at two years postoperatively were retrospectively analyzed. Results. No significant differences in blood loss, intra- and postoperative complications, or implant position were observed between the two groups. Superficial wound infection rate was higher in the obese group (8.1%) compared to the nonobese group (1.2%) (p = 0.007) and relative risk of reoperation was 2.59 (95% confidence interval 0.68 to 9.91). One periprosthetic joint infection was reported in the obese group. Set-up time in the operating table and mean operating time were higher in morbidly obese patients. Functional outcomes and patient-related outcome measurements were superior in the obese group (mean increase of HHS was 52.19 (SD 5.95) vs 45.1 (SD 4.42); p < 0.001), and mean increase of International Hip Outcome Tool (12-items) was 56.8 (SD 8.88) versus 55.2 (SD 5.85); p = 0.041). Conclusion. Our results suggest that THA in morbidly obese patients can be safely and effectively performed via the DAA by experienced surgeons. Cite this article: Bone Jt Open 2022;3(1):4–11

Aims. To establish whether there was a consensus among the members of the Hip Society (HS) on the role of direct anterior approach (DAA) contemporary primary total hip arthroplasty (THA). Methods. An online survey was sent to all 112 active and senior members of the HS, to which 71 members responded. The survey was constructed to determine whether they believed that evidence-based medicine proves, in modern clinical practice, that the DAA has significant benefits compared to risks when contrasted with other approaches. In addition, they were asked if they currently used the DAA. Results. While only 16.9% (12/71) of respondents had been trained in a generic anterior approach during residency, 49.3% (35/71) had used the DAA in their clinical practice in the past or were using it at the present time. Unexpectedly, 42.9% (15/35) of respondents who had used the DAA in the past had abandoned it by the time of this survey. Only 22.5% (16/71) of all respondents believed that evidence-based medicine proves that the DAA has significant benefits compared to risks in contrast to other approaches. Conclusion. A comprehensive literature review found only three prospective randomized clinical trials (RCT) comparing the DAA with another approach with greater than one-year follow-up. Two showed minor benefits within the early postoperative period only, and one of those showed poorer mid-term results. Most of the published comparison studies with short follow-up show longer surgical times and greater blood loss for the DAA, and many three-month comparison studies show higher complication rates for the DAA using a proprietary traction table. The complications included problems with wound healing, lateral femoral cutaneous nerve injury, femoral component loosening, and femoral fractures. Because of the lack of evidence from RCTs showing superiority of the DAA over other approaches and reports of higher complications, the opinion of a large majority (77.5%; 55/71) of HS surgeons was that the DAA lacks sufficient evidence to warrant its use. Cite this article: Bone Joint J 2020;102-B(7 Supple B):57–61

Aims. It is not known whether preservation of the capsule of the hip positively affects patient-reported outcome measures (PROMs) in total hip arthroplasty using the direct anterior approach (DAA-THA). A recent randomized controlled trial found no clinically significant difference at one year postoperatively. This study aimed to determine whether preservation of the anterolateral capsule and anatomical closure improve the outcome and revision rate, when compared with resection of the anterolateral capsule, at two years postoperatively. Methods. Two consecutive groups of patients whose operations were performed by the senior author were compared. The anterolateral capsule was resected in the first group of 430 patients between January 2012 and December 2014, and preserved and anatomically closed in the second group of 450 patients between July 2015 and December 2017. There were no other technical changes between the two groups. Patient characteristics, the Charlson Comorbidity Index (CCI), and surgical data were collected from our database. PROM questionnaires, consisting of the Oxford Hip Score (OHS) and Core Outcome Measures Index (COMI-Hip), were collected two years postoperatively. Data were analyzed with generalized multiple regression analysis. Results. The characteristics, CCI, operating time, and length of stay were similar in both groups. There was significantly less blood loss in the capsular preservation group (p = 0.037). The revision rate (n = 3, (0.6%) in the resected group, and 1 (0.2%) in the preserved group) did not differ significantly (p = 0.295). Once adjusted for demographic and surgical factors, the preserved group had significantly worse PROMs: + 0.24 COMI-Hip (p < 0.001) and -1.6 OHS points (p = 0.017). However, the effect sizes were much smaller than the minimal clinically important differences (MCIDs) of 0.95 and 5, respectively). The date of surgery (influencing, for instance, the surgeon’s age) was not a significant factor. Conclusion. Based on the MCID, the lower PROMs in the capsular preservation group do not seem to have clinical relevance. They do not, however, confirm the expected benefit of capsular preservation reported for the posterolateral approach. Cite this article: Bone Joint J 2022;104-B(7):826–832

Aims. The direct anterior approach (DAA) for total hip arthroplasty (THA) has potential advantages over other approaches and is most commonly performed with the patient in the supine position. We describe a technique for DAA THA with the patient in the lateral decubitus position and report the early clinical and radiological outcomes, the characteristics of the learning curve, and perioperative complications. Methods. All primary DAA THAs performed in the lateral position by a single surgeon over a four-year period from the surgeon’s first case using the technique were identified from a prospectively collected database. Modified Harris Hip Scores (mHHS) were collected to assess clinical outcome, and routine radiological analysis was performed. Retrospective review of the medical records identified perioperative complications, the characteristics of the learning curve, and revisions. Results. A total of 257 patients were included in the study. Their mean age was 60 years (SD 9.0). A total of 164 (64%) were female. The mean mHHS improved significantly from 52.1 (SD 16.2) preoperatively to 94.4 (SD 11) at a follow-up of one year (p < 0.001), with 212 of 225 patients (94%) achieving a minimal clinically important difference (MCID) (> 8 points). Radiological evaluation showed a mean leg length discrepancy of 2.6 mm (SD 5.9) and a mean difference in femoral offset of 0.2 mm (SD 4.9). A total of 234/243 acetabular components (96.3%) were positioned within Lewinnek’s safe zone. Analysis of operating time, blood loss, the position of the components, and complications did not identify a learning curve. A total of 14 patients (5.4%) had a major perioperative complication and three (1.2%) required revision THA. There were no major neurovascular complications and no dislocations. Conclusion. We have described and analyzed a surgical technique for undertaking DAA THA in the familiar lateral decubitus position using a routine operating table, positioning devices, and instrumentation, and shown that it can be performed safely and effectively under these circumstances. Cite this article: Bone Joint J 2021;103-B(7 Supple B):53–58

Only limited data are available regarding the infiltration of local anaesthetic for total hip arthroplasty (THA), and no studies were performed for THA using the anterior approach. . In this prospective, randomised placebo-controlled study we investigated the effect of both standard and reverse infiltration of local anaesthetic in combination with the anterior approach for THA. The primary endpoint was the mean numeric rating score for pain four hours post-operatively. In addition, we recorded the length of hospital stay, the operating time, the destination of the patient at discharge, the use of pain medication, the occurrence of side effects and pain scores at various times post-operatively. Between November 2012 and January 2014, 75 patients were included in the study. They were randomised into three groups: standard infiltration of local anaesthetic, reversed infiltration of local anaesthetic, and placebo. There was no difference in mean numeric rating score for pain four hours post-operatively (p = 0.87). There were significantly more side effects at one and eight hours post-operatively in the placebo group (p = 0.02; p = 0.03), but this did not influence the mobilisation of the patients. There were no differences in all other outcomes between the groups. We found no clinically relevant effect when the infiltration of local anaesthetic with ropivacaine and epinephrine was used in a multimodal pain protocol for THA using the anterior approach. Cite this article: Bone Joint J 2015; 97-B:734–40

Aims. Lateral femoral cutaneous nerve (LFCN) injury is a potential complication after the direct anterior approach for total hip arthroplasty (DAA-THA). The aim of this study was to determine how the location of the fasciotomy in DAA-THA affects LFCN injury. Methods. In this trial, 134 patients were randomized into a lateral fasciotomy (n = 67) or a conventional fasciotomy (n = 67) group. This study was a dual-centre, double-blind, prospective randomized controlled two-arm trial with parallel group design and a 1:1 allocation ratio. The primary endpoint was the presence of LFCN injury, which was determined by the presence of numbness, decreased sensation, tingling, jolt-like sensation, or pain over the lateral aspect of the thigh, excluding the surgical scar, using a patient-based questionnaire. The secondary endpoints were patient-reported outcome measures (PROMs) using the Western Ontario and McMaster Universities osteoarthritis index (WOMAC), Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ), and the Forgotten Joint Score-12 (FJS-12). Assessments were obtained three months after surgery. Results. The incidence of LFCN injury tended to be lower in the lateral fasciotomy group (p = 0.089). In the lateral fasciotomy group, there were no significant differences in the mean PROM scores between patients with and without LFCN injury (FJS-12: 54.42 (SD 15.77) vs 65.06 (SD 26.14); p = 0.074; JHEQ: 55.21 (SD 12.10) vs 59.72 (SD 16.50); p = 0.288; WOMAC: 82.45 (SD 6.84) vs 84.40 (SD 17.91); p = 0.728). In the conventional fasciotomy group, there were significant differences in FJS-12 and JHEQ between patients with and without LFCN injury (FJS-12: 43.21 (SD 23.08) vs 67.28 (SD 20.47); p < 0.001; JHEQ: 49.52 (SD 13.97) vs 59.59 (SD 15.18); p = 0.012); however, there was no significant difference in WOMAC (76.63 (SD 16.81) vs 84.16 (SD 15.94); p = 0.107). Conclusion. The incidence of LFCN injury at three months after THA was comparable between the lateral and conventional fasciotomy groups. Further studies are needed to assess the long-term effects of these approaches. Cite this article: Bone Joint J 2023;105-B(12):1252–1258

Aims. Use of the direct anterior approach (DAA) for total hip arthroplasty (THA) has increased in recent years due to proposed benefits, including a lower risk of dislocation and improved early functional recovery. This study investigates the dislocation rate in a non-selective, consecutive cohort undergoing THA via the DAA without any exclusion or bias in patient selection based on habitus, deformity, age, sex, or fixation method. Methods. We retrospectively reviewed all patients undergoing THA via the DAA between 2011 and 2017 at our institution. Primary outcome was dislocation at minimum two-year follow-up. Patients were stratified by demographic details and risk factors for dislocation, and an in-depth analysis of dislocations was performed. Results. A total of 2,831 hips in 2,205 patients were included. Mean age was 64.9 years (24 to 96), mean BMI was 29.2 kg/m. 2. (15.1 to 53.8), and 1,595 patients (56.3%) were female. There were 11 dislocations within one year (0.38%) and 13 total dislocations at terminal follow-up (0.46%). Five dislocations required revision. The dislocation rate for surgeons who had completed their learning curve was 0.15% compared to 1.14% in those who had not. The cumulative periprosthetic infection and fracture rates were 0.53% and 0.67%, respectively. Conclusion. In a non-selective, consecutive cohort of patients undergoing THA via the DAA, the risk of dislocation is low, even among patients with risk factors for instability. Our data further suggest that the DAA can be safely used in all hip arthroplasty patients without an increased risk of wound complications, fracture, infection, or revision. The inclusion of seven surgeons increases the generalizability of these results. Cite this article: Bone Joint J 2021;103-B(7 Supple B):38–45

Aims. This study aimed to use intraoperative free electromyography to examine how the placement of a retractor at different positions along the anterior acetabular wall may affect the femoral nerve during total hip arthroplasty (THA) when undertaken using the direct anterior approach (THA-DAA). Methods. Intraoperative free electromyography was performed during primary THA-DAA in 82 patients (94 hips). The highest position of the anterior acetabular wall was defined as the “12 o’clock” position (middle position) when the patient was in supine position. After exposure of the acetabulum, a retractor was sequentially placed at the ten, 11, 12, one, and two o’clock positions (right hip; from superior to inferior positions). Action potentials in the femoral nerve were monitored with each placement, and the incidence of positive reactions (defined as explosive, frequent, or continuous action potentials, indicating that the nerve was being compressed) were recorded as the primary outcome. Secondary outcomes included the incidence of positive reactions caused by removing the femoral head, and by placing a retractor during femoral exposure; and the incidence of femoral nerve palsy, as detected using manual testing of the strength of the quadriceps muscle. Results. Positive reactions were significantly less frequent when the retractor was placed at the ten (15/94; 16.0%), 11 (12/94; 12.8%), or 12 o’clock positions (19/94; 20.2%), than at the one (37/94; 39.4%) or two o’clock positions (39/94; 41.5%) (p < 0.050). Positive reactions also occurred when the femoral head was removed (28/94; 29.8%), and when a retractor was placed around the proximal femur (34/94; 36.2%) or medial femur (27/94; 28.7%) during femoral exposure. After surgery, no patient had reduced strength in the quadriceps muscle. Conclusion. Placing the anterior acetabular retractor at the one or two o’clock positions (right hip; inferior positions) during THA-DAA can increase the rate of electromyographic signal changes in the femoral nerve. Thus, placing a retractor in these positions may increased the risk of the development of a femoral nerve palsy. Cite this article: Bone Joint J 2022;104-B(2):193–199

Aims. Optimal exposure through the direct anterior approach (DAA) for total hip arthroplasty (THA) conducted on a regular operating theatre table is achieved with a standardized capsular releasing sequence in which the anterior capsule can be preserved or resected. We hypothesized that clinical outcomes and implant positioning would not be different in case a capsular sparing (CS) technique would be compared to capsular resection (CR). Methods. In this prospective trial, 219 hips in 190 patients were randomized to either the CS (n = 104) or CR (n = 115) cohort. In the CS cohort, a medial based anterior flap was created and sutured back in place at the end of the procedure. The anterior capsule was resected in the CR cohort. Primary outcome was defined as the difference in patient-reported outcome measures (PROMs) after one year. PROMs (Harris Hip Score (HHS), Hip disability and Osteoarthritis Outcome Score (HOOS), and Short Form 36 Item Health Survey (SF-36)) were collected preoperatively and one year postoperatively. Radiological parameters were analyzed to assess implant positioning and implant ingrowth. Adverse events were monitored. Results. At one year, there was no difference in HSS (p = 0.728), HOOS (Activity Daily Life, p = 0.347; Pain, p = 0.982; Quality of Life, p = 0.653; Sport, p = 0.994; Symptom, p = 0.459), or SF-36 (p = 0.338). Acetabular component inclination (p = 0.276) and anteversion (p = 0.392) as well as femoral component alignment (p = 0.351) were similar in both groups. There were no dislocations, readmissions, or reoperations in either group. The incidence of psoas tendinitis was six cases in the CS cohort (6%) and six cases in the CR cohort (5%) (p = 0.631). Conclusion. No clinical differences were found between resection or preservation of the anterior capsule when performing a primary THA through the DAA on a regular theatre table. In case of limited visibility during the learning curve, it might be advisable to resect a part of the anterior capsule. Cite this article: Bone Joint J 2021;103-B(2):321–328

Aims. It has been suggested that the direct anterior approach (DAA) should be used for total hip arthroplasty (THA) instead of the posterior approach (PA) for better early functional outcomes. We conducted a value-based analysis of the functional outcome and associated perioperative costs, to determine which surgical approach gives the better short-term outcomes and lower costs. Methods. This meta-analysis was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol and the Cochrane Handbook. Several online databases were searched. Non-stratified and stratified meta-analyses were conducted to test the confounding biases in the studies which were included. The mean cost and probability were used to determine the added costs of perioperative services. Results. The DAA group had significantly longer operating times (p < 0.001), reduced length of hospital stay by a mean of 13.4 hours (95% confidence interval (CI) 9.12 to 18; p < 0.001), and greater blood loss (p = 0.030). The DAA group had significantly better functional outcome at three (p < 0.001) and six weeks (p = 0.006) postoperatively according to the Harris Hip Score (HHS). However, there was no significant difference between the groups for the HHS at six to eight weeks (p = 0.230), 12 weeks (p = 0.470), six months (p = 0.740), and one year (p = 0.610), the 12-Item Short Form Survey (SF-12) physical score at six weeks (p = 0.580) and one year (p = 0.360), SF-12 mental score at six weeks (p = 0.170) and one year (p = 0.960), and University of California and Los Angeles (UCLA) activity scale at 12 weeks (p = 0.250). The mean non-stratified and stratified difference in costs for the operating theatre time and blood transfusion were $587.57 (95% CI 263.83 to 1,010.29) to $887.04 (95% CI 574.20 to 1,298.88) and $248.38 (95% CI 1,003.40 to 1,539.90) to $1,162.41 (95% CI 645.78 to 7,441.30), respectively, more for the DAA group. However, the mean differences in costs for the time in hospital were $218.23 and $192.05, respectively, less for the DAA group. Conclusion. The use of the DAA, rather than the PA, in THA has earlier benefits for function and pain. However, these are short-lasting, with no significant differences seen at later intervals. In addition the limited benefits were obtained with higher cumulative costs for DAA. Cite this article: Bone Joint J 2021;103-B(6):1078–1087

A complete cement mantle is important for the longevity of a total hip replacement. In the minimally-invasive direct anterior approach used at the Innsbruck University hospital, the femoral component has to be inserted into the femoral canal by an angulated movement. In a cadaver study, the quality and the extent of the cement mantle surrounding 13 Exeter femoral components implanted straight through a standard anterolateral transgluteal approach were compared with those of 13 similar femoral components implanted in an angulated fashion through a direct anterior approach. A third-generation cementing technique was used. The inner and outer contours of the cement mantles was traced from CT scans and the thickness and cross-sectional area determined. In no case was the cement mantle incomplete. The total mean thickness of the cement mantle was 3.62 mm (95% confidence interval 3.59 to 3.65). The mean thickness in the group using the minimally-invasive approach was 0.16 mm less than that in the anterolateral group. The distribution of the thickness was similar in the two groups. The mean thickness was less on the anteromedial and anterolateral aspect than on the posterior aspect of the femur. There is no evidence that the angulated introduction of Exeter femoral components in the direct anterior approach in cadavers compromises the quality, extent or thickness of the cement mantle

The April 2023 Spine Roundup³⁶⁰ looks at: Percutaneous transforaminal endoscopic discectomy versus microendoscopic discectomy; Spine surgical site infections: a single debridement is not enough; Lenke type 5, anterior, or posterior: systematic review and meta-analysis; Epidural steroid injections and postoperative infection in lumbar decompression or fusion; Noninferiority of posterior cervical foraminotomy versus anterior cervical discectomy; Identifying delays to surgical treatment for metastatic disease; Cervical disc replacement and adjacent segment disease: the NECK trial; Predicting complication in adult spine deformity surgery.