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Bone & Joint Research
Vol. 13, Issue 4 | Pages 184 - 192
18 Apr 2024
Morita A Iida Y Inaba Y Tezuka T Kobayashi N Choe H Ike H Kawakami E

Aims

This study was designed to develop a model for predicting bone mineral density (BMD) loss of the femur after total hip arthroplasty (THA) using artificial intelligence (AI), and to identify factors that influence the prediction. Additionally, we virtually examined the efficacy of administration of bisphosphonate for cases with severe BMD loss based on the predictive model.

Methods

The study included 538 joints that underwent primary THA. The patients were divided into groups using unsupervised time series clustering for five-year BMD loss of Gruen zone 7 postoperatively, and a machine-learning model to predict the BMD loss was developed. Additionally, the predictor for BMD loss was extracted using SHapley Additive exPlanations (SHAP). The patient-specific efficacy of bisphosphonate, which is the most important categorical predictor for BMD loss, was examined by calculating the change in predictive probability when hypothetically switching between the inclusion and exclusion of bisphosphonate.


Bone & Joint Open
Vol. 5, Issue 3 | Pages 154 - 161
1 Mar 2024
Homma Y Zhuang X Watari T Hayashi K Baba T Kamath A Ishijima M

Aims

It is important to analyze objectively the hammering sound in cup press-fit technique in total hip arthroplasty (THA) in order to better understand the change of the sound during impaction. We hypothesized that a specific characteristic would present in a hammering sound with successful fixation. We designed the study to quantitatively investigate the acoustic characteristics during cementless cup impaction in THA.

Methods

In 52 THAs performed between November 2018 and April 2022, the acoustic parameters of the hammering sound of 224 impacts of successful press-fit fixation, and 55 impacts of unsuccessful press-fit fixation, were analyzed. The successful fixation was defined if the following two criteria were met: 1) intraoperatively, the stability of the cup was retained after manual application of the torque test; and 2) at one month postoperatively, the cup showed no translation on radiograph. Each hammering sound was converted to sound pressures in 24 frequency bands by fast Fourier transform analysis. Basic patient characteristics were assessed as potential contributors to the hammering sound.


Bone & Joint Open
Vol. 3, Issue 12 | Pages 960 - 968
23 Dec 2022
Hardwick-Morris M Wigmore E Twiggs J Miles B Jones CW Yates PJ

Aims

Leg length discrepancy (LLD) is a common pre- and postoperative issue in total hip arthroplasty (THA) patients. The conventional technique for measuring LLD has historically been on a non-weightbearing anteroposterior pelvic radiograph; however, this does not capture many potential sources of LLD. The aim of this study was to determine if long-limb EOS radiology can provide a more reproducible and holistic measurement of LLD.

Methods

In all, 93 patients who underwent a THA received a standardized preoperative EOS scan, anteroposterior (AP) radiograph, and clinical LLD assessment. Overall, 13 measurements were taken along both anatomical and functional axes and measured twice by an orthopaedic fellow and surgical planning engineer to calculate intraoperator reproducibility and correlations between measurements.


Bone & Joint Research
Vol. 11, Issue 12 | Pages 873 - 880
1 Dec 2022
Watanabe N Miyatake K Takada R Ogawa T Amano Y Jinno T Koga H Yoshii T Okawa A

Aims

Osteoporosis is common in total hip arthroplasty (THA) patients. It plays a substantial factor in the surgery’s outcome, and previous studies have revealed that pharmacological treatment for osteoporosis influences implant survival rate. The purpose of this study was to examine the prevalence of and treatment rates for osteoporosis prior to THA, and to explore differences in osteoporosis-related biomarkers between patients treated and untreated for osteoporosis.

Methods

This single-centre retrospective study included 398 hip joints of patients who underwent THA. Using medical records, we examined preoperative bone mineral density measures of the hip and lumbar spine using dual energy X-ray absorptiometry (DXA) scans and the medications used to treat osteoporosis at the time of admission. We also assessed the following osteoporosis-related biomarkers: tartrate-resistant acid phosphatase 5b (TRACP-5b); total procollagen type 1 amino-terminal propeptide (total P1NP); intact parathyroid hormone; and homocysteine.


Bone & Joint Open
Vol. 3, Issue 10 | Pages 759 - 766
5 Oct 2022
Schmaranzer F Meier MK Lerch TD Hecker A Steppacher SD Novais EN Kiapour AM

Aims

To evaluate how abnormal proximal femoral anatomy affects different femoral version measurements in young patients with hip pain.

Methods

First, femoral version was measured in 50 hips of symptomatic consecutively selected patients with hip pain (mean age 20 years (SD 6), 60% (n = 25) females) on preoperative CT scans using different measurement methods: Lee et al, Reikerås et al, Tomczak et al, and Murphy et al. Neck-shaft angle (NSA) and α angle were measured on coronal and radial CT images. Second, CT scans from three patients with femoral retroversion, normal femoral version, and anteversion were used to create 3D femur models, which were manipulated to generate models with different NSAs and different cam lesions, resulting in eight models per patient. Femoral version measurements were repeated on manipulated femora.


Bone & Joint Research
Vol. 12, Issue 9 | Pages 571 - 579
20 Sep 2023
Navacchia A Pagkalos J Davis ET

Aims

The aim of this study was to identify the optimal lip position for total hip arthroplasties (THAs) using a lipped liner. There is a lack of consensus on the optimal position, with substantial variability in surgeon practice.

Methods

A model of a THA was developed using a 20° lipped liner. Kinematic analyses included a physiological range of motion (ROM) analysis and a provocative dislocation manoeuvre analysis. ROM prior to impingement was calculated and, in impingement scenarios, the travel distance prior to dislocation was assessed. The combinations analyzed included nine cup positions (inclination 30-40-50°, anteversion 5-15-25°), three stem positions (anteversion 0-15-30°), and five lip orientations (right hip 7 to 11 o’clock).


Bone & Joint Open
Vol. 5, Issue 6 | Pages 479 - 488
6 Jun 2024
Paksoy A Meller S Schwotzer F Moroder P Trampuz A Imiolczyk J Perka C Hackl M Plachel F Akgün D

Aims

Current diagnostic tools are not always able to effectively identify periprosthetic joint infections (PJIs). Recent studies suggest that circulating microRNAs (miRNAs) undergo changes under pathological conditions such as infection. The aim of this study was to analyze miRNA expression in hip arthroplasty PJI patients.

Methods

This was a prospective pilot study, including 24 patients divided into three groups, with eight patients each undergoing revision of their hip arthroplasty due to aseptic reasons, and low- and high-grade PJI, respectively. The number of intraoperative samples and the incidence of positive cultures were recorded for each patient. Additionally, venous blood samples and periarticular tissue samples were collected from each patient to determine miRNA expressions between the groups. MiRNA screening was performed by small RNA-sequencing using the miRNA next generation sequencing (NGS) discovery (miND) pipeline.


Bone & Joint Research
Vol. 12, Issue 9 | Pages 590 - 597
20 Sep 2023
Uemura K Otake Y Takashima K Hamada H Imagama T Takao M Sakai T Sato Y Okada S Sugano N

Aims

This study aimed to develop and validate a fully automated system that quantifies proximal femoral bone mineral density (BMD) from CT images.

Methods

The study analyzed 978 pairs of hip CT and dual-energy X-ray absorptiometry (DXA) measurements of the proximal femur (DXA-BMD) collected from three institutions. From the CT images, the femur and a calibration phantom were automatically segmented using previously trained deep-learning models. The Hounsfield units of each voxel were converted into density (mg/cm3). Then, a deep-learning model trained by manual landmark selection of 315 cases was developed to select the landmarks at the proximal femur to rotate the CT volume to the neutral position. Finally, the CT volume of the femur was projected onto the coronal plane, and the areal BMD of the proximal femur (CT-aBMD) was quantified. CT-aBMD correlated to DXA-BMD, and a receiver operating characteristic (ROC) analysis quantified the accuracy in diagnosing osteoporosis.


Bone & Joint Open
Vol. 4, Issue 12 | Pages 964 - 969
19 Dec 2023
Berwin JT Duffy SDX Gargan MF Barnes JR

Aims

We assessed the long-term outcomes of a large cohort of patients who have undergone a periacetabular osteotomy (PAO), and sought to validate a patient satisfaction questionnaire for use in a PAO cohort.

Methods

All patients who had undergone a PAO from July 1998 to February 2013 were surveyed, with several patient-reported outcome measures (PROMs) and radiological measurements of preoperative acetabular dysplasia and postoperative correction also recorded. Patients were asked to rate their level of satisfaction with their operation in achieving pain relief, restoration of activities of daily living, ability to perform recreational activity, and their overall level of satisfaction with the procedure.


Bone & Joint Research
Vol. 13, Issue 4 | Pages 193 - 200
23 Apr 2024
Reynolds A Doyle R Boughton O Cobb J Muirhead-Allwood S Jeffers J

Aims

Manual impaction, with a mallet and introducer, remains the standard method of installing cementless acetabular cups during total hip arthroplasty (THA). This study aims to quantify the accuracy and precision of manual impaction strikes during the seating of an acetabular component. This understanding aims to help improve impaction surgical techniques and inform the development of future technologies.

Methods

Posterior approach THAs were carried out on three cadavers by an expert orthopaedic surgeon. An instrumented mallet and introducer were used to insert cementless acetabular cups. The motion of the mallet, relative to the introducer, was analyzed for a total of 110 strikes split into low-, medium-, and high-effort strikes. Three parameters were extracted from these data: strike vector, strike offset, and mallet face alignment.


Bone & Joint Open
Vol. 4, Issue 5 | Pages 306 - 314
3 May 2023
Rilby K Mohaddes M Kärrholm J

Aims

Although the Fitmore Hip Stem has been on the market for almost 15 years, it is still not well documented in randomized controlled trials. This study compares the Fitmore stem with the CementLeSs (CLS) in several different clinical and radiological aspects. The hypothesis is that there will be no difference in outcome between stems.

Methods

In total, 44 patients with bilateral hip osteoarthritis were recruited from the outpatient clinic at a single tertiary orthopaedic centre. The patients were operated with bilateral one-stage total hip arthroplasty. The most painful hip was randomized to either Fitmore or CLS femoral component; the second hip was operated with the femoral component not used on the first side. Patients were evaluated at three and six months and at one, two, and five years postoperatively with patient-reported outcome measures, radiostereometric analysis, dual-energy X-ray absorptiometry, and conventional radiography. A total of 39 patients attended the follow-up visit at two years (primary outcome) and 35 patients at five years. The primary outcome was which hip the patient considered to have the best function at two years.


Bone & Joint Open
Vol. 3, Issue 9 | Pages 684 - 691
1 Sep 2022
Rodriguez S Shen TS Lebrun DG Della Valle AG Ast MP Rodriguez JA

Aims

The volume of ambulatory total hip arthroplasty (THA) procedures is increasing due to the emphasis on value-based care. The purpose of the study is to identify the causes for failed same-day discharge (SDD) and perioperative factors leading to failed SDD.

Methods

This retrospective cohort study followed pre-selected patients for SDD THA from 1 August 2018 to 31 December 2020. Inclusion criteria were patients undergoing unilateral THA with appropriate social support, age 18 to 75 years, and BMI < 37 kg/m2. Patients with opioid dependence, coronary artery disease, and valvular heart disease were excluded. Demographics, comorbidities, and perioperative data were collected from the electronic medical records. Possible risk factors for failed SDD were identified using multivariate logistic regression.


Bone & Joint Open
Vol. 5, Issue 6 | Pages 514 - 523
24 Jun 2024
Fishley W Nandra R Carluke I Partington PF Reed MR Kramer DJ Wilson MJ Hubble MJW Howell JR Whitehouse SL Petheram TG Kassam AM

Aims

In metal-on-metal (MoM) hip arthroplasties and resurfacings, mechanically induced corrosion can lead to elevated serum metal ions, a local inflammatory response, and formation of pseudotumours, ultimately requiring revision. The size and diametral clearance of anatomical (ADM) and modular (MDM) dual-mobility polyethylene bearings match those of Birmingham hip MoM components. If the acetabular component is satisfactorily positioned, well integrated into the bone, and has no surface damage, this presents the opportunity for revision with exchange of the metal head for ADM/MDM polyethylene bearings without removal of the acetabular component.

Methods

Between 2012 and 2020, across two centres, 94 patients underwent revision of Birmingham MoM hip arthroplasties or resurfacings. Mean age was 65.5 years (33 to 87). In 53 patients (56.4%), the acetabular component was retained and dual-mobility bearings were used (DM); in 41 (43.6%) the acetabulum was revised (AR). Patients underwent follow-up of minimum two-years (mean 4.6 (2.1 to 8.5) years).


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 24 - 24
23 Jun 2023
Byrd JWT Jones KS Bardowski EA
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Partial thickness abductor tendon tears are a significant source of recalcitrant laterally based hip pain. For those that fail conservative treatment, the results of endoscopic repair are highly successful with minimal morbidity. The principal burden is the protracted rehabilitation that is necessary as part of the recovery process. There is a wide gap between failed conservative treatment and successful surgical repair. It is hypothesized that a non-repair surgical strategy, such as a bioinducitve patch, could significantly reduce the burden associated recovery from a formal repair. Thus, the purpose of this study is to report the preliminary results of this treatment strategy.

Symptomatic partial thickness abductor tendon tears are treated conservatively, including activity modification, supervised physical therapy and ultrasound guided corticosteroid injections. Beginning in January 2022, patients undergoing hip arthroscopy for intraarticular pathology who also had persistently symptomatic partial thickness abductor tendon tears, were treated with adjunct placement of a bioinducitve (Regeneten) patch over the tendon lesion from the peritrochanteric space. The postop rehab protocol is dictated by the intraarticular procedure performed. All patients are prospectively assessed with a modified Harris Hip Score (mHHS) and iHOT and the tendon healing response examined by ultrasound.

Early outcomes will be presented on nine consecutive cases.

Conclusions - Will be summarized based on the preliminary outcomes to be reported.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 35 - 35
23 Jun 2023
Lavernia C Patron LP Lavernia CJ Gibian J Hong T Bendich I Cook SD
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Fracture of contemporary femoral stems is a rare occurrence. Earlier THR stems failed due to design issues or post manufacturing heat treatments that weakened the core metal. Our group identified and analyzed 4 contemporary fractured femoral stems after revision surgery in which electrochemical welds contributed to the failure.

All four stems were proximally porous coated titanium alloy components. All failures occurred in the neck region post revision surgery in an acetabular cup exchange. All were men and obese. The fractures occurred at an average of 3.6 years post THR redo (range, 1.0–6.5 years) and 8.3 years post index surgery (range, 5.5–12.0 years). To demonstrate the effect of electrocautery on retained femoral stems following revision surgery, we applied intermittent electrosurgical currents at three intensities (30, 60, 90 watts) to the polished neck surface of a titanium alloy stem under dry conditions.

At all power settings, visible discoloration and damage to the polished neck surface was observed. The localized patterns and altered metal surface features exhibited were like the electrosurgically-induced damage priorly reported.

The neck regions of all components studied displayed extensive mechanical and/or electrocautery damage in the area of fracture initiation. The use of mechanical instruments and electrocautery was documented to remove tissues in all 4 cases.

The combination of mechanical and electrocautery damage to the femoral neck and stem served as an initiation point and stress riser for subsequent fractures. The electrocautery and mechanical damage across the fracture site observed occurred iatrogenically during revision surgery. The notch effect, particularly in titanium alloys, due to mechanical and/or electrocautery damage, further reduced the fatigue strength at the fractured femoral necks. While electrocautery and mechanical dissection is often required during revision THA, these failures highlight the need for caution during this step of the procedure in cases where the femoral stem is retained.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 6 - 6
23 Jun 2023
Callary S Barends J Solomon LB Nelissen R Broekhuis D Kaptein B
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The best treatment method of large acetabular bone defects at revision THR remains controversial. Some of the factors that need consideration are the amount of residual pelvic bone removed during revision; the contact area between the residual pelvic bone and the new implant; and the influence of the new acetabular construct on the centre of rotation of the hip. The purpose of this study was to compare these variables in two of the most used surgical techniques used to reconstruct severe acetabular defects: the trabecular metal acetabular revision system (TMARS) and a custom triflanged acetabular component (CTAC).

Pre- and post-operative CT-scans were acquired from 11 patients who underwent revision THR with a TMARS construct for a Paprosky IIIB defect, 10 with pelvic discontinuity, at Royal Adelaide Hospital. The CT scans were used to generate computer models to virtually compare the TMARS and CTAC constructs using a semi-automated method. The TMARS construct model was calculated using postoperative CT scans while the CTAC constructs using the preoperative CT scans. The bone contact, centre of rotation, inclination, anteversion and reamed bone differences were calculated for both models.

There was a significant difference in the mean amount of bone reamed for the TMARS reconstructions (15,997 mm3) compared to the CTAC reconstructions (2292 mm3, p>0.01). There was no significant difference between overall implant bone contact (TMARS 5760mm2 vs CTAC 5447mm2, p=0.63). However, there was a significant difference for both cancellous (TMARS 4966mm2 vs CTAC 2887mm2, p=0.008) and cortical bone contact (TMARS 795mm2 vs CTAC 2560mm2, p=0.001). There was no difference in inclination and anteversion achieved. TMARS constructs resulted on average in a centre of rotations 7.4mm more lateral and 4.0mm more posterior.

Modelling of two different reconstructions of Paprosky IIIB defects demonstrated potential important differences between all variables investigated.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 9 - 9
23 Jun 2023
Lachiewicz PF Skalla LA Purcell KP
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Severe heterotopic ossification (grade III and IV) after contemporary total hip arthroplasty (THA) requiring excision is very uncommon. We performed a systematic review of the literature, and report a new case series with operative treatment after primary uncemented THA.

A systematic review identified papers describing patients who had excision of heterotopic ossification (HO) after contemporary THA, defined as performed after 1988. Concepts of hip arthroplasty, heterotopic ossification, and surgical excision were searched in MEDLINE, Embase, and Scopus, from database inception to November 2022. Inclusion criteria were: articles that included specific patient data on grade of heterotopic ossification, operative procedure, and prophylaxis. Studies were screened for inclusion by two independent reviewers. Extracted data included demographic data, interval from index surgery to excision, clinical results, and complications. One surgeon performed reoperation for ankylosis of primary THA in three patients with severe pain and deformity.

Seven case series or case report studies were included. There were 41 patients, with grade III or IV HO, that had excision, and in five patients, revision of a component was also performed. Perioperative prophylaxis was irradiation alone in 10 patients, irradiation and indomethacin in 10, and indomethacin alone in 21 patients. At a mean follow-up time of 14.8 months, definition of the results was not uniform, and range of motion was improved, but relief of pain was inconsistent. There was one dislocation, one gastrointestinal complication, and two recurrences. Treatment of the three patients, with wide excision of peri-articular bone, selective exchange of components, and peri-operative irradiation prophylaxis, was successful in improving motion and deformity.

There is insufficient data on the treatment of severe symptomatic HO after contemporary THA. Prophylaxis with low-dose irradiation was successful to prevent recurrence. Multicenter studies will be needed to determine the optimum timing and prognosis for treatment.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 12 - 12
23 Jun 2023
Yee AHF Chan VWK Chiu K
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Uncemented femoral components have been used in total hip arthroplasties (THAs) for over three decades. Data on long-term performance of hydroxyapatite-coated femoral stems is however limited. This study reports the survivorship of a collarless, straight, hydroxyapatite-coated femoral stem (Omnifit HA, Osteonic) with a minimum of 20 years of follow-up.

We reviewed the results of 165 THAs using Omnifit HA in 138 patients performed between August 1993 and December 1999. The mean age at surgery was 46 years (range 20 – 77 years). Avascular necrosis was the most common cause of THA, followed by ankylosing spondylitis and primary osteoarthritis. The mean follow-up was 22 years (range 20–31 years). At 20 and 25 years, 113 arthroplasties (91 patients) and 63 arthroplasties (55 patients) were available for follow-up respectively, while others had deceased or were lost to follow-up.

Kaplan-Meier survivorship analysis was performed to evaluate the survival of the femoral component. Radiographs were reviewed at regular intervals, and implant stability was evaluated using Engh classification.

Seven out of 165 stems were revised upon the latest follow-up; that included one case of aseptic loosening with revision done at 15 years, three peri-prosthetic fractures, two infections, and one recurrent dislocation.

At 20 years, survivorship with revision of the femoral stem for any cause and aseptic loosening as the endpoint was 96.0% (95% CI, 92.6 – 99.5%) and 98.4% (95% CI, 96.2 – 100%) respectively. At 25 years, the corresponding survivorship rates were 94.5% (95% CI, 91.9 – 97.3%) and 98.1% (95% CI, 95.7 – 99.6%) respectively.

Radiographic findings of stable bony fixation were seen in 86 stems (76.1%) and those of loosening in 4 stems (3.5%) at 20 years. All patients with radiographic signs of loosening were asymptomatic and did not require revision.

The Omnifit HA femoral stem offered promising long-term survivorship into the third decade.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 13 - 13
23 Jun 2023
Furnes O Lygre SHL Hallan G Fenstad AM
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The Norwegian Arthroplasty Register (NAR) started collecting data on total hip arthroplasty (THA) in 1987. Very long-term results of implants for THA are scarce. We aimed to show long-term results for the three most used femoral stems, operated from 1987.

We included the uncemented Corail femoral stem (n=66,309) and the cemented Exeter stem (n=35,050) both of which are currently in frequent use. In addition, we included the Charnley stem (n=32,578, in use until 2014). To ensure comparable conditions, stems fixated with low viscosity cement and stems revised due to infections were excluded. Differences in risk of revision (all reasons and stem revisions) were assessed with Kaplan-Meier and Cox regression analyses with adjustment for possible confounding from age, sex and diagnosis (OA, other). Stem revision was defined as a revision caused by loosening of the stem, dislocation, osteolysis in the femur, or periprosthetic femur fracture, and in which the femoral component was removed or exchanged.

The median and max follow-up for Corail, Exeter and Charnley were 6.3 (33.1), 8.0 (34.2) and 13.1 (34.3) respectively. Thirty years survival estimates for Corail, Exeter and Charnley stems were 88.6% (CI:85.8–90.9%), 86.7% (83.7–89.2%) and 87.1% (85.4–88.5%) respectively with stem revision as endpoint, and 56.1% (CI:53.1–59.1%), 73.3% (70.5–76.1%) and 80.2% (78.4–82.0%) with all THA revisions as endpoint. Compared to the Corail, the Exeter (HRR=1.3, CI:1.2–1.4) and the Charnley (HRR=1.9, CI:1.7–2.1) had a significant higher risk of stem revision. Women 75 years and older had better results with the cemented stems. Analyses accounting for competing risk from other causes of revision did not alter the findings.

The uncemented Corail stem performed well in terms of stem revisions for stem-related revision causes compared to two frequently used cemented stems with very long follow-up. The differences between the three stems were small.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 15 - 15
23 Jun 2023
Ricotti RG Flevas D Sokrab R Vigdorchik JM Sculco TP Sculco PK
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Periprosthetic femur fracture (PFF) is a major complication following total hip arthroplasty (THA) that carries significant morbidity, mortality, and economic burden. Currently, uncemented stems are highly preferred in primary THA, but have been associated with higher risk of PFF compared to cemented stems. The use of collared stems in uncemented primary THA has shown promise in reducing PFF rates postoperatively.

This retrospective study included 2,294 uncemented primary THAs using the posterior approach performed by two attending surgeons from January 2016 to December 2022. Both surgeons switched from a collarless femoral stem design to a collared design in May 2020. Data was collected regarding stem design, frequency of PFF, and requirement for revision surgery. Periprosthetic fractures were identified and confirmed using medical records and/or radiographic imaging. Fracture rates and percentages between collared and collarless stems were then analyzed. A Fisher's Exact Test was performed to determine if there was a significant association between collared and collarless stem use on PFF rates.

A total of 2,294 uncemented primary THAs performed by 2 surgeons were eligible for analysis. 903 (39.4%) patients received a collared stem, and 1,391 (60.6%) patients received a collarless stem. In total, 14 (0.6%) PFFs occurred over the study period. There was 1 fracture (0.1%) out of 903 collared stems, and 13 fractures (0.9%) out of 1,391 collarless stems (p = 0.012).

Collared stems were associated with a significant decrease in PFF rate when compared to collarless stems in uncemented primary THA. Future studies are encouraged to continue to investigate PFF and other complication rates with the use of a collared stem design.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 17 - 17
23 Jun 2023
Schreurs BW van Veghel MH van der Koelen RE Hannink G Rijnen WH
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Although data on uncemented short stems are available, studies on cemented short-stemmed THAs are limited. These cemented short stems may have inferior long-term outcomes and higher femoral component fracture rates. Hence, we examined the long-term follow-up of cemented short Exeter stems used in primary THA.

Within the Exeter stem range, 7 stems have a stem length of 125 mm or less. These stems are often used in small patients, in young patients with a narrow femoral canal or patients with anatomical abnormalities. Based on our local database, we included 394 consecutive cemented stems used in primary THA (n=333 patients) with a stem length ≤125 mm implanted in our tertiary referral center between 1993 and December 2021. We used the Dutch Arthroplasty Registry (LROI) to complete and cross-check the data. Kaplan-Meier survival analyses were performed to determine 20-year survival rates with stem revision for any reason, for septic loosening, for aseptic loosening and for femoral component fracture as endpoints.

The proportion of male patients was 21% (n=83). Median age at surgery was 42 years (interquartile range: 30–55). The main indication for primary THA was childhood hip diseases (51%). The 20-year stem survival rate of the short stem was 85.4% (95% CI: 73.9–92.0) for revision for any reason and 96.2% (95%CI: 90.5–98.5) for revision for septic loosening. No stems were revised for aseptic femoral loosening. However, there were 4 stem fractures at 6.6, 11.6, 16.5 and 18.2 years of follow-up. The stem survival with femoral component fracture as endpoint was 92.7% (CI: 78.5–97.6) at 20 years.

Cemented short Exeter stems in primary THA show acceptable survival rates at long-term follow-up. Although femoral component fracture is a rare complication of a cemented short Exeter stem, orthopaedic surgeons should be aware of its incidence and possible risk factors.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_11 | Pages 42 - 42
7 Jun 2023
Holleyman R Bankes M Witt J Khanduja V Malviya A
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Periacetabular osteotomy (PAO) is an established treatment for developmental hip dysplasia (DDH) in young adults and can also be utilised in the management of femoroacetabular impingement (FAI) with acetabular retroversion. This study used a national registry to assess the outcomes of PAO for DDH and FAI.

PAOs recorded in the UK Non-Arthroplasty Hip Registry between 2012 and November 2022 were identified along with recorded patient and surgical characteristics. Cases were grouped according to the primary pathology (DDH or FAI). Patient reported outcome measures (PROMs) captured included the International Hip Outcome Tool (iHOT)-12 (primary outcome) and the EuroQol-5 Dimensions (EQ-5D) index preoperatively and at 6 months, 1, 2, and 5 years post-operatively.

1,087 PAOs were identified; 995 for DDH (91%), 98 for FAI (9%). Most patients (91%) were female. The DDH group were significantly older (mean 31.7 years) than the FAI group (25.4 years) but had similar body mass index (mean 25.7kg/m2). Overall, significant (all p<0.0001) iHOT-12 and EQ-5D improvement (delta) vs baseline pre-operative scores were achieved at 6 months (mean iHOT-12 improvement +27.4 (95%CI 25.3 to 29.5); n=515) and maintained out to 5 years (+30.0 (21.4 to 38.6); n=44 [9.8% of those eligible for follow-up at 5 years]), at which point 71% and 55% of patients continued to demonstrate a score improvement greater than or equal to the minimum clinically important difference (≥13 points) and substantial clinical benefit (≥28 points) for iHOT-12 respectively.

This study demonstrates excellent functional outcomes following PAO undertaken for DDH and FAI in the short to medium term in a large national registry.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_11 | Pages 45 - 45
7 Jun 2023
Howard D Manktelow B DeSteiger R Skinner J Ashford R
Full Access

Ceramic bearing fractures are rare events, but mandate revision and implantation of new bearings. Revisions using metal heads have been reported to lead to gross volumetric head wear (due to abrasive retained ceramic micro-debris), cobalt toxicity, multi-organ failure and death. Such complications are widely published (50+ reports), yet we know that patients continue to be put at risk. Using data from the NJR and AOANJRR, this study seeks to compare the risk of re-revision and death by revision bearing combination following a ceramic bearing fracture.

Data were extracted from the NJR and AOANJRR, identifying revisions for ceramic bearing fracture. Subsequent outcomes of survival, re-revision and death were compared between revision bearing combinations (ceramic-on-ceramic, ceramic-on-polyethylene, and metal-on-polyethylene).

366 cases were available for analysis from the NJR dataset (MoP=34, CoP=112, CoC=221) and 174 from the AOANJRR dataset (MoP=17, CoP=44, CoC=113). The overall incidence rate of adverse outcome (revision or death) was 0.65 for metal heads and 0.23 for ceramic head articulations (p=0.0012) across the whole time period (NJR). Kaplan-Meir survival estimates demonstrate an increased risk of both re-revision and death where a metal head has been used vs a ceramic head following revision for ceramic fracture.

There are few decisions in arthroplasty surgery that can lead to serious harm or death for our patients, but revision using a metal head following ceramic bearing fracture is one of them. This study enhances the signal of what is already known but previously only reported as inherently low-level evidence (case reports and small series) due to event rarity. Use of a metal head in revision for ceramic fracture represents an avoidable patient safety issue, which revision guidelines should seek to address.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_11 | Pages 47 - 47
7 Jun 2023
Malik-Tabassum K Ahmed M Jones HW Gill K Board T Gambhir A
Full Access

Musculoskeletal disorders have been recognised as common occupational risks for all orthopaedic surgeons. The nature of tasks performed by hip surgeons often requires both forceful and repetitive manoeuvres, potentially putting them at higher risk of musculoskeletal injuries compared to other orthopaedic sub-specialities. This study aimed to investigate the prevalence of musculoskeletal conditions among hip surgeons and evaluate the association between their workplace and lifestyle factors and musculoskeletal health.

An online questionnaire consisting of 22 questions was distributed to UK-based consultant hip surgeons via email and social media platforms. This survey was completed by 105 hip surgeons.

The mean age of the respondents was 49 years (range 35–69), with an average of 12 years (range 1–33) in service. 94% were full-time and 6% worked part-time. 49% worked at a district general hospital, 49% at a tertiary centre and 4% at a private institution. 80% were on the on-call rota and 69% had additional trauma commitments. 91% reported having one or more, 50% with three or more and 13% with five or more musculoskeletal conditions. 64% attributed their musculoskeletal condition to their profession. The most common musculoskeletal conditions were base of thumb arthritis (22%), subacromial impingement (20%), degenerative lumbar spine (18%) and medial or lateral epicondylitis (18%). 60% stated that they experienced lower back pain. Statistical analysis showed that being on the on-call rota was significantly (P<0.001) associated with a higher musculoskeletal burden. Regular resistance and/or endurance training and BMI<30 were statistically significant protective factors (P<0.001).

Over the last few decades, most of the hip-related literature has focused on improving outcomes in patients, yet very little is known about the impact of hip surgery on the musculoskeletal health of hip surgeons. This study highlights a high prevalence of musculoskeletal conditions among UK-based hip surgeons. Hip surgeons have a pivotal role to play in the ongoing recovery of elective orthopaedics services. There is a pressing need for the identification of preventative measures and improvement in the surgical environment of our hip surgeons.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 1 - 1
23 Jun 2023
Parker J Horner M Jones SA
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Contemporary acetabular reconstruction in major acetabular bone loss often involves the use of porous metal augments, a cup-cage construct or custom implant. The aims of this study were: To determine the reproducibility of a reconstruction algorithm in major acetabular bone loss. To determine the subsequent success of reconstruction performed in terms of re-operation, all-cause revision and Oxford Hip Score (OHS) and to further define the indications for custom implants in major acetabular bone loss.

Consecutive series of Paprosky Type III defects treated according to a reconstruction algorithm. IIIA defects were planned to use a superior augment and hemispherical cup.

IIIB defects were planned to receive either augment and cup, cup-cage or custom implant.

105 procedures in cohort 100 patients (5 bilateral) with mean age 73 years (42–94).

IIIA defects (50 cases) − 72.0% (95%CI 57.6–82.1) required a porous metal augment the remainder treated with a hemispherical cup alone. IIIB defects (55 cases) 71.7% (95%CI 57.6–82.1) required either augments or cup-cage. 20 patients required a hemispherical cup alone and 6 patients received a custom-made implant.

Mean follow up of 7.6 years. 6 re-revisions were required (4 PJI, 2 peri-prosthetic fractures & 1 recurrent instability) with overall survivorship of 94.3% (95% CI 97.4–88.1) for all cause revision. Single event dislocations occurred in 3 other patients so overall dislocation rate 3.8%. Mean pre-op OHS 13.8 and mean follow-up OHS 29.8.

Custom implants were used in: Mega-defects where AP diameter >80mm, complex discontinuity and massive bone loss in a small pelvis (i.e., unable to perform cup-cage)

A reconstruction algorithm can >70% successfully predict revision construct which thereafter is durable with a low risk of re-operation. Jumbo cup utilized <1/3 of cases when morphology allowed. The use of custom implants has been well defined in this series and accounts for <5% of cases.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 37 - 37
23 Jun 2023
Díaz-Dilernia F Slullitel P Zanotti G Comba F Buttaro M
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We sought to determine the short to medium-term clinical and radiographic outcomes using a short stem in young adults with a proximal femoral deformity (PFD).

We prospectively studied 31 patients (35 hips) with PFDs treated with an uncemented primary THA using a short stem with cervicometaphyseal fixation between 2011–2018. There were 19 male (23 hips) and 12 female (12 hips) patients, with a mean BMI of 26.7±4.1 kg/m2. Twelve cases had a previous surgical procedure, and six of them were failed childhood osteotomies. Mean age of the series was 44±12 years, mean follow-up was 81±27 months and no patients were lost to follow-up. PFDs were categorized according to a modified Berry´s classification. Average preoperative leg-length discrepancy (LLD) was −16.3 mm (−50 to 2).

At a mean time of 81 months of follow-up, survival rate was 97% taking revision of the stem for any reason and 100% for aseptic loosening as endpoints. No additional femoral osteotomy was required in any case. Average surgical time was 66 minutes (45 to 100). There was a significant improvement in the mHHS score when comparing preoperative and postoperative values (47.3±10.6 vs. 92.3±3.7, p=0.0001). Postoperative LLD was in average 1 mm (−9 to 18) (p=0.0001). According to Engh's criteria, all stems were classified as stable without signs of loosening. Postoperative complications included 1 pulmonary embolism, 1 neurogenic sciatic pain, 1 transient sciatic nerve palsy that recovered completely after six months, and 2 acute periprosthetic joint infections. One patient suffered a Vancouver B2 periprosthetic femoral fracture 45 days after surgery and was revised with a modular distally fixed uncemented fluted stem.

A type 2B short stem evidenced promising outcomes at short to medium-term follow up in young adult patients with PFDs, avoiding the need for corrective osteotomies and a revision stem.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 81 - 81
23 Jun 2023
MacDonald SJ Alatassi R Somerville L Howard JL
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The Canadian Cardiovascular Society (CCS) recommends performing daily troponin testing on postoperative days 0 through 3 for noncardiac surgical patients to decrease the mortality rate due to myocardial injury. Indications for testing include:

->65 yo

-45-64 yo with significant cardiovascular disease

-a Revised Cardiac Risk Index score (RCRI) > 1

Troponin elevation > 30 ng/L is termed “myocardial injury after noncardiac surgery” (MINS).

The study objective was to determine the prognostic relevance of applying CCS recommendations.

669 patients undergoing THA were included in the study. Based on the CCS recommendation there were 4 patient Groups depending on whether or not they met the MINS screening protocol criteria and whether or not it was applied:

-A - met & applied (n=181)

-B - met & not applied (n=248)

-C – not met & applied (n=10)

-D – not met & not applied (n=230)

307 (45.8%) males and 363 (54.2%) females with an average age of 67.8 years were included. Group A- 24% incidence (43 patients) of troponin rise & 5% incidence (9 patients) of cardiac complications. Group B- 0.4% incidence (1 patient) of cardiac complications.

Groups A + B – representing all patients who should have had the MINS screening protocol applied according to the CCS recommendations − 10 (2.3%) patients developed cardiac complication and one (0.2%) patient death

MINS screening protocol group (A & C) LOS was 4.0 days compared to 1.4 days for those not screened (p-value: <0.001).

Applying the CCS MINS screening protocol to elective THA patients added no benefit in predicting/preventing postoperative cardiac events but was associated with a significant increase in LOS. Following current CCS recommendations without more specifications and clinical evidence is unwarranted.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 85 - 85
23 Jun 2023
de Mello F Kadirkamanathan V Wilkinson JM
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Successful estimation of postoperative PROMs prior to a joint replacement surgery is important in deciding the best treatment option for a patient. However, estimation of the outcome is associated with substantial noise around individual prediction. Here, we test whether a classifier neural network can be used to simultaneously estimate postoperative PROMs and uncertainty better than current methods.

We perform Oxford hip score (OHS) estimation using data collected by the NJR from 249,634 hip replacement surgeries performed from 2009 to 2018. The root mean square error (RMSE) of the various methods are compared to the standard deviation of outcome change distribution to measure the proportion of the total outcome variability that the model can capture. The area under the curve (AUC) for the probability of the change score being above a certain threshold was also plotted.

The proposed classifier NN had a better or equivalent RMSE than all other currently used models. The threshold AUC shows similar results for all methods close to a change score of 20 but demonstrates better accuracy of the classifier neural network close to 0 change and greater than 30 change, showing that the full probability distribution performed by the classifier neural network resulted in a significant improvement in estimating the upper and lower quantiles of the change score probability distribution. Consequently, probabilistic estimation as performed by the classifier NN is the most adequate approach to this problem, since the final score has an important component of uncertainty.

This study shows the importance of uncertainty estimation to accompany postoperative PROMs prediction and presents a clinically-meaningful method for personalised outcome that includes such uncertainty estimation.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 87 - 87
23 Jun 2023
Rolfson O Nåtman J Rogmark C Sundberg M Mohaddes M Kärrholm J W-Dahl A
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In 1975, Sweden started registering primary knee replacement surgeries based on the personal identity number. Individual-based registrations of primary total hip replacements started in 1992 and for hemiarthroplasties the registration started in 2006. The completeness of these registrations is estimated at 98% during the last 10-year period. The long history and high completeness allow for accurate calculations of population-based prevalence of joint replacement and trends over time.

We used all data on primary joint replacements available in the Swedish Arthroplasty Register. The prevalence was calculated using number of alive patients with 1) at least one joint replacement 2) at least one hip replacement 3) at least one knee replacement at the end of each year from 2010 – 2021. Publicly available population numbers were retrieved from Statistics Sweden. We calculated total prevalence and prevalence per age in years.

By the end of 2021, 3.2% of the Swedish population had at least one hip or knee replacement. This was an increase from 2.5% in 2010. Among 80-year-old, the prevalence was 17.5% for any joint replacement. For both hip and knee replacement and all ages, the prevalence was higher for women. For knee replacement, the 2021 prevalence peaked at the age of 89 (9,4%) while the prevalence continuously increased with age for hip replacements.

A considerable proportion of the Swedish elderly population is living with at least one hip or knee replacement. The prevalence has increased during the last 12-year period for both hips and knees. An increasing prevalence may also affect the incidence of fractures and infections. Knowledge about the prevalence is fundamental for planning future demand for primary and revision hip and knee replacement.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_11 | Pages 28 - 28
7 Jun 2023
Kumar VRS Gopalannair V Dehbozorgi S Bhaskar D
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There is a surge of patients on the waiting-list for primary total hip replacement (THR), due to unprecedented reduction of elective activity caused by COVID-19. A higher incidence of femoral head collapse (FC) and acetabular erosion (AE) leading to increase in pain and instability as well as requirement of more complex surgery and potentially higher risk to patients was noted in this period. Rapidly progressive Arthritis (RPA) of the hip is a known entity often described as progression of joint space narrowing greater than 2mm over one year time period. The study aims to identify any potential relationship between waiting time and establishment of femoral head collapse and/ or acetabular erosion.

A retrospective review of arthroplasty surgeon's waiting list during COVID. Serial hip radiographs recorded between February 2020 and February 2022 were analysed.

FC was quantified as a percentage of the femoral head radius, while AE was assessed by drawing two parallel lines, one through both tear drops and the other through superior most aspect of intact acetabulum, parallel to the inter tear-drop line and expressed as percentage of normal side.

Only 105 patients out of 264 patients added to the waiting list had elective arthroplasty for hip/knee. Only 35 patients out of 90 listed for THR, had the surgery.

36 of 90 (40%) were found to have developed FC and fitted the criteria for RPA. Acetabular erosion was seen in 19 (21%). Therefore 53% (19 of 36) of those who developed FC progressed to AE.

Incidence of collapse was higher in females (32%), with mean age of 62 (range 51–81), compared to 21% in males with mean age 59 (range 53–87). Mean extent of femoral head collapse was 20% (10 – 44%).

A significant proportion of patients added to waiting list during COVID developed RPA of the hip with 40% having femoral head collapse and 21% progressing to acetabular erosion leading to a complex case-mix. Patients on long waiting lists need regular x-ray checks/PROMS since significant proportion progress to FC and Acetabular Erosion.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_11 | Pages 30 - 30
7 Jun 2023
Harris E Farrow L Martin C Adam K
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Hip fracture represents a significant challenge, placing increasing pressure on health and social care services in Scotland. This study establishes the ‘historic’ hip fracture burden, namely, the annual number of hip fractures in Scotland, and respective incidence, between 2017 – 2021. Furthermore, the ‘projected’ hip fracture burden and incidence from 2022 – 2029 was estimated, to inform future capacity and funding of health and social care services.

The number of individuals with a hip fracture in Scotland between 2017 and 2021 was identified through the Scottish Hip Fracture Audit, enabling the annual number of hip fractures and respective incidence between 2017 – 2021 to be calculated. Projection modelling was performed using Exponential Smoothing and Auto Regressive Integrated Moving Average to estimate the number of hip fractures occurring annually from 2022 – 2029. A combined average projection was employed to provide a more accurate forecast. Accounting for predicted changes within the population demographics of Scotland, the projected hip fracture incidence up to 2029 was calculated.

Between 2017 and 2021 the annual number of hip fractures in Scotland increased from 6675 to 7797 (15%), with an increase in incidence from 313 to 350 per 100,000 (11%) of the at-risk population. Hip fracture was observed to increase across all groups, notably males, and the 70–79 and 80–89 age cohorts. By 2029, the combined average projection estimated the annual number of hip fractures at 10311, with an incidence rate of 463 per 100,000, representing a 32% increase from 2021. The largest percentage increase in hip fracture by 2029 occurs in the 70–79 and 80–89 age cohorts (57% and 53% respectively). Based upon these projections, overall length of hospital stay following hip fracture will increase by 60699 days per annum by 2029, incurring an additional cost of at least £25 million.

Projection modelling demonstrates the annual number of hip fractures in Scotland will increase substantially by 2029, with significant implications for health and social care services. This increase in hip fracture burden and incidence is influenced strongly by changing population demographics, primarily an ageing population.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_11 | Pages 32 - 32
7 Jun 2023
Howgate D Roberts PG Palmer A Price A Taylor A Rees J Kendrick B
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Primary total hip replacement (THR) is a successful and common operation which orthopaedic trainees must demonstrate competence in prior to completion of training. This study aimed to determine the impact of operating surgeon grade and level of supervision on the incidence of 1-year patient mortality and all-cause revision following elective primary THR in a large UK training centre.

National Joint Registry (NJR) data for all elective primary THR performed in a single University Teaching Hospital from 2005–2020 were used, with analysis performed on the 15-year dataset divided into 5-year temporal periods (B1 2005–2010, B2 2010–2015, B3 2015–2020). Outcome measures were mortality and revision surgery at one year, in relation to lead surgeon grade, and level of supervision for trainee-led operations.

9999 eligible primary THR were undertaken, of which 5526 (55.3%) were consultant led (CL), and 4473 (44.7%) trainees led (TL). Of TL, 2404 (53.7%) were non-consultant supervised (TU), and 2069 (46.3%) consultant supervised (TS). The incidence of 1-year patient mortality was 2.05% (n=205), and all-cause revision was 1.11% (n=111). There was no difference in 1-year mortality between TL (n=82, 1.8%) and CL (n=123, 2.2%) operations (p=0.20, OR 0.78, CI 0.55–1.10). The incidence of 1-year revision was not different for TL (n=56, 1.3%) and CL (n=55, 1.0%) operations (p=0.15, OR 1.37, CI 0.89–2.09). Overall, there was no temporal change for either outcome measure between TL or CL operations. A significant increase in revision within 1-year was observed in B3 between TU (n=17, 2.7%) compared to CL (n=17, 1.0%) operations (p=0.005, OR 2.81, CI 1.35–5.87).

We found no difference in 1-year mortality or 1-year all-cause revision rate between trainee-led primary THR and consultant-led operations over the entire fifteen-year period. However, unsupervised trainee led THR in the most recent 5-year block (2015–2020) has a significantly increased risk of early revision, mainly due to instability and prosthetic joint infection. This suggests that modern surgical training is having a detrimental effect on THR patient outcomes. More research is needed to understand the reasons if this trend is to be reversed.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 51 - 51
23 Jun 2023
Adeyemo EA Riepen DW Collett GA Au BK Huo MH
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The current evidence favors replacement for the treatment of displaced femoral neck fractures in the older patients. Controversies remain whether total hip replacement (THR), or hemiarthroplasty (HA) would result in better outcomes. The purpose of this study is to compare the outcomes, and the complications in patients who underwent THR or HA for displaced femoral neck fractures.

There were 345 consecutive patients who had undergone either a THR or HA at a single institution. THR was done in 137, and HA was done in 208 patients, respectively. Standard peri-operative data were collected.

The mean values for the data in the THR group are: age 69 years, ASA 2.7, OR time was 99 minutes, estimated blood loss 354 ml, and the length of stay 8 days. The mean values for the data in the HA group are: age 75 years, ASA 3.0, OR time 88 minutes, estimated blood loss 200 ml, and the length of stay 10 days. The overall complications were 8.8% (THR), and 9.1% (HA), respectively. The mortality rates for the patients were: at the 1-year (9.5% THR vs 16.3% HA), at the 3-year (15.3% THR vs 24.0% HA), and at the 5-year (19.7% THR vs 26.9% HA), respectively.

Our data demonstrated similar peri-operative data and short-term complications between the two groups. There was a difference in the mortality rates between the two groups at all 3-time intervals following the surgery. This could be a reflection of the patient selection bias for each of the operations.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 53 - 53
23 Jun 2023
Schemitsch EH Nowak LL De Beer J Brink O Poolman R Mehta S Stengel D Bhandari M
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We aimed to use data from a randomized controlled trial (RCT) comparing the sliding hip screw vs. intramedullary nailing (IMN) for trochanteric fractures to examine complication rates between those managed with a short vs. long IMN.

This is a secondary analysis using one arm of an RCT of patients ≥18 years with trochanteric fractures. We examined differences in fracture-related (femoral shaft fracture, implant failure, surgical site infection (SSI), nonunion, limb shortening, and pain) and medical (organ failure, respiratory distress, stroke, deep vein thrombosis [DVT] gastrointestinal upset, pneumonia, myocardial infarction, sepsis, or urinary tract infection) adverse events (AE), and readmission between short vs. long IMNs.

We included 412 trochanteric fracture patients, 339 (82.2%) of whom received a short (170mm–200mm) nail, while 73 (17.7%) received a long (260mm–460 mm) nail. Patients in the long group were more likely to be admitted from home (vs. an institution), and have comorbidities, or more complex fracture types.

Patients in the long group had higher rates of fracture-related AE (12.3%) vs. the short group (3.5%). Specifically, SSI (5.5% vs. 0.3%) and pain (2.7% vs. 0.0%) were significantly higher in the long group. Patients in the long group were also more likely to develop DVT (2.7% vs. 0.3%), and be readmitted to the hospital (28.8% vs. 20.7%).

Following covariable adjustment, long nails remained associated with a higher odds of fracture-related AE (5.11, 1.96–13.33) compared to short nails. We found no association between the adjusted odds of readmission and nail length (1.00, 0.52–1.94).

Our analyses revealed that trochanteric fracture patients managed with long IMN nails may have a higher odds of fracture-related AE compared to short nails. Future research is required to validate these findings with larger event rates, and further optimize IMN for trochanteric fracture patients.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 54 - 54
23 Jun 2023
Shaath MK Yawman J Anderson T Avilucea F Langford J Munro M Haidukewych GJ
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Intertrochanteric fractures are common, accounting for nearly 30% of all fracture related admissions. Some have suggested that these fractures should be treated in community hospitals so as not to tax the resources of Level One trauma centers. Since many factors predictive of fixation failure are related to technical aspects of the surgery, the purpose of this study was to compare radiographic parameters after fixation comparing trauma fellowship trained surgeons to non-fellowship trained community surgeons to see if these fractures can be treated successfully in either setting.

Using our hospital system's trauma database, we identified 100 consecutive patients treated with cephalomedullary nails by traumatologists, and 100 consecutive patients treated by community surgeons. Quality of reduction, neck shaft angle (NSA), tip-to apex distance (TAD) were compared.

The mean TAD for the trauma group was 10mm compared to 21mm for the community group (p<0.001). The mean postoperative NSA for the trauma group was 133 degrees compared to 127 degrees for the community group (p<0.001). The mean difference in the NSA of the fractured side compared to the normal hip was 2.5 degrees of valgus in the trauma group compared to 5 degrees of varus for the community group (p<0.001). There were 93 good reductions in the trauma group compared to 19 in the community group (p<0.001). There were no poor reductions in the trauma group and 49 poor reductions in the community group (p<0.001).

Fellowship trained traumatologists achieved significantly more accurate reductions and implant placement during cephalomedullary nailing of intertrochanteric hip fractures.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_11 | Pages 1 - 1
7 Jun 2023
Gaston P Clement N Ohly N Macpherson G Hamilton D
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In this RCT the primary aim was to assess whether a short (125mm) Exeter V40 stem offered an equivalent hip specific function compared to the standard (150mm) stem when used for cemented total hip arthroplasty (THA). Secondary aims were to evaluate health-related quality of life (HRQoL), patient satisfaction, stem height and alignment, radiographic loosening, and complications between the two stems.

A prospective multicentre double-blind randomised control trial was conducted. During a 15-month period, 220 patients undergoing THA were randomised to either a standard (n=110) or short (n=110) stem Exeter. There were no significant (p≥0.065) differences in preoperative variables between the groups. Functional outcomes and radiographic assessment were undertaken at 1- and 2-years.

There were no differences (p=0.428) in hip specific function according to the Oxford hip score at 1-year (primary endpoint) or at 2-years (p=0.767) between the groups. The short stem group had greater varus angulation (0.9 degrees, p=0.003) when compared to the standard group and were more likely (odds ratio 2.42, p=0.002) to have varus stem alignment beyond one standard deviation from the mean. There were no significant (p≥0.083) differences in the Forgotten joint scores, EuroQol-5-Dimension, EuroQol-VAS, Short form 12, patient satisfaction, complications, stem height or radiolucent zones at 1 or 2-years between the groups.

The Exeter short stem offers equivalent hip specific function, HRQoL, patient satisfaction, and limb length when compared to the standard stem at 2-years post-operation. However, the short stem was associated with a greater rate of varus malalignment which may influence future implant survival.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 59 - 59
23 Jun 2023
Hernigou P
Full Access

The variables involved in a robotic THA can exceed 52: many parameters as pelvic orientation with CT scan, templating, offset, and leg-length, acetabular reaming, femoral osteotomy, mapping the anatomy; predefining safe zones, robotic execution, femoral head size, thickness of PE etc. with several variables for each parameter, with a total number of variables exceeding 52. This familiar number is the number of cards in a standard deck. The number of possible combinations (factorial 52! = 10^67) to shuffle the cards (and may be to perform a THA) is greater than the number of atoms on earth! Thinking that artificial intelligence and robotics can solve these problems, some surgeons and implant manufacturers have turned to artificial intelligence and robotics.

We asked two questions:1) can robot with artificial intelligence really process 52 variables that represent 10^67 combinations? 2) the safety of the technology was ascertained by interrogating Food and Drug Administration (FDA) database about software-related recalls in computer-assisted and robotic arthroplasty [1], between 2017 and 2022.

The best computers can only calculate around 100 thousand billion combinations (10^14), and with difficulty: it takes more than 100 days to arrive at this number of digits (10^14) after the decimal point for the number π (pi). We can, therefore, expect the robot to be imperfect.

For the FDA software-related recalls, 4634 units were involved. The FDA determined root causes were: software design (66.6%), design change (22.2%), manufacturing deployment (5.6%), design manufacturing process (5.6%). Among the manufacturers’ reasons for recalls, a specific error was declared in 88.9%. a coding error in 43.8%. 94.4% software-related recalls were classified as class 2. Return of the device was the main action taken by firms (44.4%), followed by software update (38.9%).

In the same period, no robot complained about its surgeon!

Hip surgeon is as intelligent as a robot and almost twice as safe.


Total hip arthroplasty has been constantly evolving with technological improvements to achieve the best survival rates. Although the new implants are under closer surveillance through processes such as Beyond Compliance, orthopaedic surgeons generally tend to look out for the latest implants with good short-term results and hope for better long-term results for these. We questioned whether such an assumption or bias is valid.

We analysed the data of Kaplan-Meier estimates of cumulative revisions of primary hip replacement by fixation, stem/cup brand and bearing combinations from the NJR 19th Annual Report published in September 2022. We performed a univariate linear regression analysis to predict the 10- and 15-year revision rates for these different hip implant combinations from the 3- and 5-year revision rates.

Thirty-seven implant combinations had their 15-year revision rates reported and 67 had the 10-year revision rates. The correlation co-efficients were 0.43 and 0.58 for the 3-year and 5-year revision rates against 15-year revision rates. Only 17% of the variance in 15-year revision rates could be predicted by a linear regression model from the 3-year revision rate and 32% from the 5-year revision rate. Corresponding values for the 10-year revision rates were 46% and 67%.

95% prediction intervals for the 15-year revision rate were +/− 3.1% from the 3-year revision rate and +/− 2.8% from the 5-year revision rate. Corresponding values for the 10-year revision rates were +/− 1.3% and +/− 1%.

19 of 37 implant combinations showed 15-year revision rate of more than 4%. Average 3-year and 5-year revision rates for this cohort was 1.0% and 1.42% compared to 1.4% and 1.9% for the rest and the difference was statistically significant.

Although average early revision rates showed small but significant difference between the groups with lower and higher 15-year revision rates, the prediction intervals for 15-year revision rates for individual hips based on their 3-year and 5-year revision rates are very wide. Three- and 5-year revision rates for primary total hip replacements are poor predictors of 15-year revision rates.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_11 | Pages 9 - 9
7 Jun 2023
Jenkinson M Meek D MacMillan S Tate R Grant MH Currie S
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Elevated blood cobalt secondary to metal-on-metal (MoM) hip arthroplasties has been shown to be a risk factor for developing cardiovascular complications including cardiomyopathy. Published case reports document cardiomyopathy in patients with blood cobalt levels as low as 13µg/l (13ppb, 221nmol/l). Clinical studies have found conflicting evidence of cobalt-induced cardiomyopathy in patients with MoM hips. Global longitudinal strain (GLS) is an echocardiography measurement known to be more sensitive than ejection fraction at diagnosing early cardiomyopathies. The extent of cardiovascular injury, as measured by GLS, in patients with elevated blood cobalt levels has not previously been examined.

Sixteen patients with documented blood cobalt ion levels above 13µg/l were identified from a regional arthroplasty database. They were matched with eight patients awaiting hip arthroplasty with no history of cobalt implants. All patients underwent electrocardiogram and echocardiogram assessment for signs of cardiomyopathy including GLS.

Patients with MoM hip arthroplasties had a mean blood cobalt level of 29µg/l (495nmol/l) compared to 0.01µg/l (0.2nmol/l) in the control group. There was no difference or correlation in ejection fraction (EF), left ventricular (LV) end systolic dimension, LV end diastolic dimension, fractional shortening, ventricular wall thickness or E/e’ ratio. However, GLS was significantly reduced in patients with MoM hip arthroplasties compared to those without (−15.2% v −18%, (MoM v control) p= 0.0125). Pearson correlation demonstrated that GLS is significantly correlated with blood cobalt level (r= 0.8742, p=0.0009).

For the first time, this study has demonstrated reduced cardiac function in the presence of normal EF as assessed by GLS in patients with elevated cobalt above 13µg/l. As GLS is a more sensitive measure of systolic function than EF, routine echocardiogram assessment including GLS should be performed in all patients with MoM hip arthroplasties and elevated blood cobalt above 13µg/l. Further work is recommended to assess if these cardiac changes are present in patients with elevated blood cobalt levels below 13µg/l.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_11 | Pages 10 - 10
7 Jun 2023
Mistry D Ahmed U Aujla R Aslam N D'Alessandro P Malik S
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Industries such as agriculture, construction and military have stringent rules about hearing protection due to the risk of noise induced hearing loss (NIHL). Due to the use of power tools, orthopaedic staff may be at risk of the same condition. The UK Health and Safety Executive (HSE) have clear standards as to what is deemed acceptable occupational noise levels on an A-weighted and C weighted scale. This review is aimed to assess evidence on noise exposure testing within Orthopaedic theatres to see if it exceeds the HSE regulations.

A targeted search of online databases PUBMED and EMBASE was conducted using Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) principles. This review was registered prospectively in PROSPERO. An eligibility criterion identifying clinical studies which assessed noise exposure for Orthopaedic staff in theatres were included. Noise exposure data was extracted from these studies and a comparison was made with A weighted and C weighted acceptable exposure levels as quoted in the HSE regulations.

Fourteen papers were deemed eligible, which reviewed 133 Orthopaedic operations and 64 Orthopaedic instruments. In total, 61% (81 of 132) of Orthopaedic operations and 70% (45 of 64) of instruments exceeded the noise regulations on an A weighted scale. 22% (10 of 46) of operations exceeded the maximum C weighted peak acceptable noise level.

Orthopaedic instruments and operations can exceed safe occupational noise levels. NHS Trusts have clear policies about noise exposure in the workplace but have yet to identify Orthopaedic theatres as a potential at risk area. Orthopaedic staff need education, monitoring and protection whereas Employers and Occupational Health should consider assessments to identify at risk staff in Orthopaedic theatres and offer preventative methods from NIHL.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 78 - 78
23 Jun 2023
Liu TWK Cheung A Chiu PKY
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Isolated liner exchange with highly crosslinked polyethylene (HXLPE) is an option to address polyethylene wear and osteolysis after total hip arthroplasty (THA). The liner can be fixed with either the original locking mechanism or cemented into the acetabular cup. Whether the method used for fixation of HXLPE liner has any bearing on the outcomes 10 to 15 years after surgery is still unclear.

Data for all patients who had undergone isolated liner exchange surgery with HXLPE in our institution between August 2000 and January 2015 were retrieved. Patients were classified according to the locking mechanism used (original locking mechanism or cemented). Survivorship and revision rates were compared among different subgroups. A total of 86 isolated liner exchanges were performed and patients had a mean duration of follow-up of 13 years (range, 5 to 22). 50 patients had the new liner cemented and the other 36 patients used the original locking mechanism.

20 patients (23.3%) had complications, with dislocation being the most common (7). 10 of them (12.6%) required re-revision surgery. Overall estimated mean survivorship was 19.2 years. There was no significant difference in the re-revision rate between original locking mechanism (11.1%) and cementation (12.0%) for the fixation of HXLPE (p=0.899). Using the Kaplan-Meier survival analysis, the revision-free survival of HXLPE fixed with original locking mechanism and cementation were 94.1% and 93.2%, respectively, at 10 years, and were 84.7% and 81.3%, respectively, at 20 years (p=0.840).

The re-revision rate and the revision-free survival of liner exchange surgery using HXLPE liner were not affected by the fixation technique used. Both cementing a HXLPE liner or using the original locking mechanism were associated with good survivorship at 13 years follow up.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 42 - 42
23 Jun 2023
Lustig S Cotte M Foissey C Asirvatham R Servien E Batailler C
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The benefit of dual mobility cup (DMC) for primary total hip arthroplasties (THA) is still controversial. This study aimed to compare 1) the complications rate, 2) the revisions rate, 3) the survival rate after monobloc DMC compared to large femoral heads (LFH) in primary THA.

Between 2010 and 2019, 2,075 primary THA using cementless DMC or LFH were included. Indications for DMC were patients older than 70 years old or with high risk of dislocation. Every other patient received a LFH. Exclusion criteria were cemented implants, femoral neck fracture, a follow-up of less than one year. 1,940 THA were analyzed: 1,149 DMC (59.2%), 791 LFH (40.8%). The mean age was 73 ±9.2 years old in DMC group and 57 ±12 in LFH group. The complications and the revisions have been assessed retrospectively.

The mean follow-up was 41.9 months ±14 [12–134]. There were significantly fewer dislocations in DMC group (n=2; 0.17%) compared to LFH group (n=8; 1%) (p=0.019). The femoral head size had no impact on the dislocations rate in LFH group (p=0.70). The overall complication rate in DMC (n=59; 5.1%) and LFH (n=53; 6.7%) were not statistically different (p=0.21). No specific complication was attributed to the DMC. In DMC group, 18 THA (1.6%) were revised versus 15 THA in LFH group (1.9%) (p= 0.71). There was no statistical difference for any cause of revisions in both groups. The cup aseptic revision-free survival rates at 5 years were 98% in DMC group and 97.3% in LFH group (p=0.78).

Monobloc DMC had a lower risk of dislocation in a high-risk population than LFH in a low-risk population at the mid-term follow-up. There was no significant risk of specific complications or revisions for DMC in a large cohort. Monobloc DMC can be safely used in a selected high-risk population.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 45 - 45
23 Jun 2023
Lieberman JR
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Modular dual mobility (DM) articulations are increasingly utilized during total hip arthroplasty (THA). However, concerns remain regarding the metal liner modularity. This study aims to correlate metal artifact reduction sequence (MARS) magnetic resonance imaging (MRI) abnormalities with serum metal ion levels in patients with DM articulations.

All patients with an asymptomatic, primary THA and DM articulation with >2-year follow-up underwent MARS-MRI of the operative hip. Each patient had serum cobalt, chromium, and titanium levels drawn. Patient satisfaction, Oxford Hip Score, and Forgotten Joint Score-12 (FJS-12) were collected. Each MARS-MRI was independently reviewed by fellowship-trained musculoskeletal radiologists blinded to serum ion levels.

Forty-five patients (50 hips) with a modular DM articulation were included with average follow-up of 3.7±1.2 years. Two patients (4.4%) had abnormal periprosthetic fluid collections on MARS-MRI with cobalt levels >3.0 μg/L. Four patients (8.9%) had MARS-MRI findings consistent with greater trochanteric bursitis, all with cobalt levels < 1.0 μg/L. A seventh patient had a periprosthetic fluid collection with normal ion levels. Of the 38 patients without MARS-MRI abnormalities, 37 (97.4%) had cobalt levels <1.0 μg/L, while one (2.6%) had a cobalt level of 1.4 μg/L. One patient (2.2%) had a chromium level >3.0 μg/L and a periprosthetic fluid collection. Of the 41 patients with titanium levels, five (12.2%) had titanium levels >5.0 μg/L without associated MARS-MRI abnormalities.

Periprosthetic fluid collections associated with elevated serum cobalt levels in patients with asymptomatic dual mobility articulations occur infrequently (4.4%), but further assessment of these patients is necessary.

Level of Evidence: Level IV


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_11 | Pages 13 - 13
7 Jun 2023
Diffley T Ferry J Sumarlie R Beshr M Chen B Clement N Farrow L
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Appropriate surgical management of hip fractures has major clinical and economic consequences. Recently IMN use has increased compared to SHS constructs, despite no clear evidence demonstrating superiority of outcome. We therefore set out to provide further evidence about the clinical and economic implications of implant choice when considering hip fracture fixation strategies.

A retrospective cohort study using Scottish hip fracture audit (SHFA) data was performed for the period 2016–2022. Patients ≥50 with a hip fracture and treated with IMN or SHS constructs at Scottish Hospitals were included. Comparative analyses, including adjustment for confounders, were performed utilising Multivariable logistic regression for dichotomous outcomes and Mann-Whitney-U tests for non-parametric data. A sub-group analysis was also performed focusing on AO-A1/A2 configurations which utilised additional regional data. Cost differences in Length of Stay (LOS) were calculated using defined costs from the NHS Scotland Costs book. In all analyses p<0.05 denoted significance.

13638 records were included (72% female). 9867 received a SHS (72%).

No significant differences were identified in 30 or 60-day survival (Odds Ratio [OR] 1.05, 95%CI 0.90–1.23; p=0.532), (OR 1.10, 95%CI 0.97–1.24; p=0.138) between SHS and IMN's.

There was however a significantly lower early mobilisation rate with IMN vs SHS (OR 0.64, 95%CI 0.59–0.70; p<0.001), and lower likelihood of discharge to domicile by day-30 post-admission (OR 0.77, 95%CI 0.71–0.84; p<0.001). Acute and overall, LOS were significantly lower for SHS vs IMN (11 vs 12 days and 20 vs 24 days respectively; p<0.001). Findings were similar across a sub-group analysis of 559 AO A1/A2 fracture configurations.

Differences in LOS potentially increases costs by £1230 per-patient, irrespective of the higher costs of IMN's v SHS.

Appropriate SHS use is associated with early mobilisation, reduced LOS and likely with reduced cost of treatment. Further research exploring potential reasons for the identified differences in early mobilisation are warranted.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 74 - 74
23 Jun 2023
Wilson JM Maradit-Kremers H Abdel MP Berry DJ Mabry TM Pagnano MW Perry KI Sierra RJ Taunton MJ Trousdale RT Lewallen DG
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The last two decades have seen remarkable technological advances in total hip arthroplasty (THA) implant design. Porous ingrowth surfaces and highly crosslinked polyethylene (HXLPE) have been expected to dramatically improve implant survivorship. The purpose of the present study was to evaluate survival of contemporary cementless acetabular components following primary THA.

16,421 primary THAs performed for osteoarthritis between 2000 and 2019 were identified from our institutional total joint registry. Patients received one of 12 contemporary cementless acetabular designs with HXLPE liners. Components were grouped based on ingrowth surface into 4 categories: porous titanium (n=10,952, mean follow-up 5 years), porous tantalum (n=1223, mean follow-up 5 years), metal mesh (n=2680, mean follow-up 6.5 years), and hydroxyapatite (HA) coated (n=1566, mean follow-up 2.4 years). Kaplan-Meier analyses were performed to assess the survivorship free of acetabular revision. A historical series of 182 Harris-Galante-1 (HG-1) acetabular components was used as reference.

The 15-year survivorship free of acetabular revision was >97% for all 4 contemporary cohorts. Compared to historical control, porous titanium (HR 0.06, 95% CI 0.02–0.17, p<0.001), porous tantalum (HR 0.09, 95%CI 0.03–0.29, p<0.001), metal mesh (HR 0.11, 95%CI 0.04–0.31, p<0.001), and HA-coated (HR 0.14, 95%CI 0.04–0.48, p=0.002) ingrowth surfaces had significantly lower risk of any acetabular revision. There were 16 cases (0.1%) of acetabular aseptic loosening that occurred in 8 (0.07%) porous titanium, 5 (0.2%) metal mesh, and 3 (0.2%) HA-coated acetabular components. 7 of the 8 porous titanium aseptic loosening cases occurred in one known problematic design. There were no cases of aseptic loosening in the porous tantalum group.

Modern acetabular ingrowth surfaces and HXLPE liners have improved on historical results at the mid-term. Contemporary designs have extraordinarily high revision-free survivorship, and aseptic loosening is now a rare complication.

At mid-term follow-up, survivorship of contemporary uncemented acetabular components is excellent and aseptic loosening occurs in a very small minority of patients.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 49 - 49
23 Jun 2023
McCalden R Pomeroy E Naudie D Vasarhelyi E Lanting B MacDonald S Howard J
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Subsidence remains a concern when utilizing modern tapered fluted titanium (TFT) femoral stems and may lead to leg length discrepancy, impingement, instability and failure to obtain stem osseointegration. This study aims to compare stem subsidence across three modern TFT stems. Our secondary aim was to investigate the influence of bicortical contact or ‘scratch fit’ on subsidence, as well as the role of intraoperative imaging in maximizing this bicortical contact and preventing stem subsidence.

A retrospective review of 271 hip arthroplasties utilizing modern TFT stems in a single institution was performed. Three stem designs were included in the analysis: one monoblock TFT stem (n=91) and two modular TFT stems (Modular A [n=90]; Modular B [n=90]). Patient demographics, Paprosky femoral bone loss classification, bi-cortical contact, utilization of intra-operative imaging and stem subsidence (comparison of initial post-operative radiograph to the latest follow up radiograph - minimum three months) were recorded.

There was no statistically significant difference in the amount of subsidence between the three stems (Monoblock: 2.33mm, Modular A: 3.43mm, Modular B: 3.02mm; p=0.191). There was no statistical difference in subsidence >5mm between stems (Monoblock: 9.9%, Modular A: 22.2%, Modular B: 16.7%). Subgroup analysis based on femoral bone loss grading showed no difference in subsidence between stems. Increased bicortical contact was strongly associated with reduced subsidence (p=0.004). Intra-operative imaging was used in 46.5% (126/271) of cases; this was not correlated with bicortical contact (p=0.673) or subsidence (p=0.521). Across all groups, only two stems were revised for subsidence (0.7%).

All three modern TFT stems were highly successful and associated with low rates of subsidence, regardless of modular or monoblock design. Surgeons should select the stem that they feel is most clinically appropriate.


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_6 | Pages 10 - 10
2 May 2024
Amer M Smith C Kumar KHS Malviya A
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Adult hip dysplasia AHD is a complex 3D pathology of lateral coverage, version and/or volume and is often associated with increased femoral anteversion. The Mckibbin index MI is the combination of acetabular version AV and femoral version FV and is used as a measure of anterior hip Stability/ Impingement(1). The Bernese Periacetabular osteotomy PAO is a powerful tool in treating AHD, but it does not address FV. De-rotational femoral osteotomies FO increases risk of complications, operative time and might condemn the patient to Secondary osteotomies to balance the gait. We aim to investigate the effect of MI and FV on PROMs in patients undergoing PAO only.

593 PAOs identified on the Local Hip preservation registry between 01/2013 and 7/2023. PAOs for retroversion, residual Perthes and those combined with FO were excluded. Patients with no available PROMS at 2 years were excluded. Independent variables were collected from E-notes and imaging including MI and FV. A multiple linear regression analysis was performed against preoperative iHot12, and iHot12 change at 2years.

The mean FV was 18.86± 12.4 SD. Mean MI was 36.07, SD 15.36. Mean preop iHot12 score was 29.83 ± 17.38 SD. Mean change in iHot12 at 2 years was+36.47 ± 28.44 SD. Females and a higher BMI were statistically correlated to a lower preoperative iHot12. A lower preop iHot12 score and a higher preop AI were correlated to a bigger change in iHot12 at 2years with statistical significance. MI and FV were not found to have a statistically significant correlation with Outcome measures,

An increased Mckibbin index and femoral anteversion were not correlated with worse outcomes at two years. PAO alone in the presence of increased femoral anteversion avoids risks associated with FO which can be performed later if required.


Total hip replacement (THR) is one of the most common and cost-effective elective surgical procedures. In the National Health Service (NHS) of England and Wales a myriad of implants for THR are offered at a variety of locally negotiated prices. This study aims to estimate the total burden of elective THR to the NHS, expenditure on implants, and different scenarios of cost changes if implant selection changed for different patient groups.

Using National Joint Registry (NJR) data and NHS reference costs, we estimated the number and expenditure of NHS funded primary and revision THR in the 10-year period 2008–2017 and forecasted the number and expenditure on THR over the next decade. Using NJR average NHS Trust prices for the different implant combinations we estimated the average cost of implants used in THRs and estimated the budget impact on NHS providers from switching to alternative implants.

The NHS spent over £4.76 billion performing 702,381 THRs between 2008–2017. The average cost of implants was £1,260 per surgery, almost a fifth of the cost of primary THR. Providing cemented implant combinations in primary elective THRs may potentially save up to £281 million over the next 10 years, whilst keeping 10-year revision risks low.

The NHS is likely to spend over £5.6 billion providing primary elective THR over the next decade. There are efficiency savings to realise in the NHS by switching to more cost-effective implant combinations available for patients undergoing primary elective THR surgery, but these will need to be balanced against the risks inherent to a change in selection of implants and surgical practice. The HIPPY programme will be conducting practice surveys, discrete choice experiments and a large randomised controlled trial of cemented, uncemented and hybrid fixation in THR for patients under 70 to answer uncertainties.


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_6 | Pages 6 - 6
2 May 2024
Langdown A Goriainov V Watson R
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Gluteal Tendinopathy is a poorly understood condition that predominantly affects post-menopausal women. It causes lateral hip pain, worse when lying on the affected side or when walking up a hill or stairs. It has been labelled ˜Greater Trochanteric Pain Syndrome” a name that recognises the lack of understanding of the condition.

Surgical reconstruction of the gluteal cuff is well established and has been undertaken numerous times over the last 16 years by the senior author (AJL). However, the quality of collagen in the tendons can be very poor and this leads to compromised results. We present the results of gluteal cuff reconstruction combined with augmentation using a bioinductive implant.

14 patients (11 female, 3 male; mean age 74.2 ± 6.3 years) with significant symptoms secondary to gluteal tendinopathy that had failed conservative treatment (ultrasound guided injection and structured physiotherapy) underwent surgical reconstruction by the senior author using an open approach. In all cases the iliotibial band was lengthened and the trochanteric bursa excised. The gluteal cuff was reattached using Healicoil anchors (3–5×4.75mm anchors; single anchors but double row repair) and then augmented using a Regeneten patch. Patients were mobilised fully weight bearing post-operatively but were asked to use crutches until they were no longer limping. All had structured post-surgery rehabilitation courtesy of trained physiotherapists.

There were no post-operative complications and all patients reported an improvement in pain levels (Visual Analogue Scale 7.8 pre-op; 2.6 post-op) and functional levels (UCLA Activity Score 3.5 pre-op; 7.1 post-op) at 6 months post surgery.

Surgery for gluteal tendinopathy produces good outcomes and the use of Regeneten as an augment for poor quality collagen is seemingly a safe, helpful addition. Further comparative studies would help clarify this.


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_6 | Pages 35 - 35
2 May 2024
Robinson M Wong ML Cassidy R Bryce L Lamb J Diamond O Beverland D
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The significance of periprosthetic fractures about a total hip arthroplasty (THA) is becoming increasingly important. Recent studies have demonstrated post-operative periprosthetic fracture rates are higher amongst cemented polished taper slip (PTS) stem designs compared to collared cementless (CC) designs.

However, in the National Joint Registry, the rate of intra-operative periprosthetic femoral fractures (IOPFF) with cementless implant systems remains higher (0.87% vs 0.42%. p <0.001) potentially leading to more post-operative complications.

This study identifies the incidence of IOPFF, the fracture subtype and compares functional outcomes and revision rates of CC femoral implants with an IOPFF to CC stems and PTS stems without a fracture.

5376 consecutive CC stem THA, carried out through a posterior approach were reviewed for IOPFF. Each fracture was subdivided into calcar fracture, greater trochanter (GT) fracture or shaft fracture.

1:1:1 matched analysis was carried out to compare Oxford scores at one year. Matching criteria included; sex (exact), age (± 1 year), American Society of Anaesthesiologists (ASA) grade (exact), and date of surgery (± 6 months).

Electronic records were used to review revision rates.

Following review of the CC stems, 44 (0.8%) were identified as having an IOPFF. Of these 30 (0.6%) were calcar fractures, 11 (0.2%) GT fractures and 3 (0.06%) were shaft fractures. There were no shaft penetrations.

Overall, no significant difference in Oxford scores at one year were observed when comparing the CC IOPFF, CC non-IOPFF and PTS groups.

There were no CC stems revised for any reason with either a calcar fracture or trochanteric fracture within the period of 8 years follow-up.

IOPFF do occur more frequently in cementless systems than cemented. The majority are calcar and GT fractures. These fractures, when identified and managed intra-operatively, do not have worse functional outcomes or revision rates compared to matched non-IOPFF cases.


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_6 | Pages 7 - 7
2 May 2024
McCabe P Baxter J O'Connor M McKenna P Murphy T Cleary M Rowan F
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The burden of metastatic disease presenting with axial skeleton lesions is exponentially rising predominantly due to advances in oncological therapies. A large proportion is these lesions are located in the proximal femora, which given its unique biomechanical architecture is problematic.

These patients are frequently comorbid and require prompt and concise decision making regarding their orthopaedic care in line with recent British Orthopaedic Association guidelines.

We present data detailing the outcomes for patients with proximal femoral metastatic disease referred and treated over a three year period in an Regional Cancer Centre.

We retrospectively reviewed a prospectively maintained database of all patients referred for discussion at MDT with axial skeletal metastatic disease. From this we isolated patients with femoral disease. Demographic data along with primary tumour and metastatic disease site were assessed. Treatment regimens were analysed and compared. Finally predicted and actual mortality data was collated.

331 patients were referred over the analysed time period, of which 99 had femoral disease. 66% of patients were managed conservatively with serial monitoring while 34% underwent operative treatment. 65% of those received an intramedullary fixation while 35% had arthroplasty performed. There was a 51:49 split male to female with Prostate, Lung and Breast being the predominant primary tumours. Concurrent spinal metastatic disease was noted in 62% of patients while visceral mets were seen in 37%. Mortality rate was 65% with an average prognosis of 388 days (1.06years) while average mortality was noted within 291 days (0.8 years).

Proximal femoral metastatic disease accounts for a large volume of the overall mets burden. There is an overall tendency towards conservative management and of those requiring surgery IM nailing was the treatment of choice. The data would indicate that outcomes for these patients are guarded and on average worse than those predicted.


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_6 | Pages 3 - 3
2 May 2024
Bayram JM Kanesan H Clement N
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The aims were to assess whether vitamin D deficiency influenced mortality risk for patients presenting with a hip fracture.

A retrospective study was undertaken including all patients aged over 50 years that were admitted with a hip fracture to a single centre during a 24-month period. Serum vitamin D levels were assessed. Patient demographics and perioperative variables and mortality were collected. Cox regression analysis (adjusting for confounding) was utilised to determine the independent association between serum vitamin D level and patient mortality.

The cohort consisted of 2075 patients with a mean age of 80.7 years and 1471 (70.9%) were female. 1510 (72.8%) patients had a serum vitamin D level taken, of which 876 (58.0%) were deficient (50nmol/l). The median follow up was 417 (IQR 242 to 651) days. During follow up there were 464 (30.7%) deaths. Survival at 1 year was significantly (p=0.003) lower for patients who were vitamin D deficient (71.7%, 95% confidence intervals (CI) 68.6 to 74.9) compared to those who were not (79.0%, 95% CI 75.9 to 82.3). Vitamin D deficiency was also independently associated with an increased mortality risk at 2-years (HR 1.25, 95% CI 1.03 to 1.53, p=0.025), but not at 1-year (p=0.057).

Hip fracture patients with vitamin D deficiency had an increased mortality risk. This risk was independent of confounders at 2 years. The role of measuring vitamin D levels in these patients is unclear. Improved public health policy about vitamin D may be required to reduce deficiency in this patient population.


MCID and PASS are thresholds driven from PROMS to reflect clinical effectiveness. Statistical significance can be derived from a change in PROMS, whereas MCID and PASS reflect clinical significance. Its role has been increasingly used in the world of young adult hip surgery with several publications determining the thresholds for Femoro-acetabular impingement FAI. To our knowledge MCID and PASS for patient undergoing PAO for dysplasia has not been reported.

593 PAOs between 1/2013 and 7/2023 were extracted from the Northumbria Hip Preservation Registry. Patients with available PROMS at 1year and/or 2years were included. PAOs for retroversion, residual Perthes and those combined with FO were excluded. MCID was calculated using the distribution method 0.5SD of baseline score(1). PASS was calculated using anchor method, ROC analysis performed, and value picked maximizing Youden index. A Logistic Regression analysis was performed to determine which independent variables correlated with achieving MCID and PASS.

The MCID threshold for iHOt12 was 8.6 with 83.4 and 86.3 % of patients achieved it at 1 and 2 years respectively. The PASS score at 1 and 2 year follow up was 43 and 44 respectively, with 72.6 and 75.2% achieving it at 1 and 2 year postop. At 2 years a Higher preop iHOT 12 was associated with not achieving MCID and PASS (p<0.05). Preop acetabular version was negatively correlated with achieving MCID and previous hip arthroscopy was negatively correlated with PASS.

The % of patients achieving MCID and PASS mimics that of FAI surgery (2). The negative correlation with preop iHOT12 reaffirms the importance of patient selection. The negative correlation of hip arthroscopy highlights the importance of having a high index of suspicion for dysplasia prior to hip arthroscopy and poorer outcomes of patients with mixed CAM and dysplasia pathology.


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_6 | Pages 64 - 64
2 May 2024
Lamb J West R Relton S Wilkinson M Pandit H
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Current estimates of periprosthetic fracture risk associated with femoral implants is mostly limited to revision only estimates and does not accurately represent stem performance. The aim of this study was to estimate the risk of surgically treated post-operative periprosthetic femoral fracture (POPFF) more accurately associated with frequently used femoral implants used for total hip arthroplasty (THA).

A cohort study of patients who underwent primary THA in England between January 1, 2004, and December 31, 2020. Periprosthetic fractures were identified from prospectively collected revision records and national procedure coding records. Survival modelling was used to estimate POPFF incidence rates, adjusting for potential confounders. Subgroup analyses were performed for patients over 70 years, with non-osteoarthritic indications, and neck of femur fracture.

POPFF occurred in 0.6% (5100/809,832) of cases during a median (IQR) follow up of 6.5 (3.9 to 9.6) years. The majority of POPFF were treated with fixation after implantation of a cemented stem. Adjusted patient time incidence rates (PTIR) for POPFF varied by stem design, regardless of cement fixation. Cemented composite beam stems (CB stems) demonstrated the lowest risk of POPFF. Collared cementless stems had an equivalent or lower rate of POPFF versus the current gold standard polished taper slip cemented stem.

POPFF account for a quarter of all revisions following primary THA. Cemented CB stems are associated with the lowest POPFF risk. Stem design is strongly associated with POPFF risk, regardless of the presence of cement. Surgeons, policymakers, and patients should consider these findings when recommending femoral implants in those most at risk of POPFF.


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_6 | Pages 60 - 60
2 May 2024
Farrow L Clement N Meek D
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Given the prolonged waits for hip arthroplasty seen across the U.K. it is important that we optimise priority systems to account for potential disparities in patient circumstances and impact. We set out to achieve this through a two-stage approach. This included a Delphi-study of patient and surgeon preferences to determine what should be considered when determining patient priority, followed by a Discrete Choice Experiment (DCE) to decide relative weighting of included attributes.

The study was conducted according to the published protocol ([https://boneandjoint.org.uk/article/10.1302/2633-1462.310.BJO-2022-0071](https://boneandjoint.org.uk/article/10.1302/2633-1462.310.BJO-2022-0071)). The Delphi study was performed online over 3 rounds with anonymous ranking and feedback. Included factors were voted as either Consensus in, Consensus out, or No Consensus• following an established scoring criterion. A final consensus meeting determined the prioritisation factors (and their levels) to be included in the DCE. The DCE was then conducted using an online platform, with surgeons performing 18 choice sets regarding which merited greater priority between two hypothetical patients. Results were collated and analysed using multinomial logit regression analysis (MNL).

For the Delphi study there were 43 responses in the first round, with a subsequent 91% participation rate. Final consensus inclusion was achieved for Pain; Mobility/Function; Activities of Daily Living; Inability to Work/Care; Length of Time Waited; Radiological Severity and Mental Wellbeing. 70 individuals subsequently contributed to the DCE, with radiological severity being the most significant factor (Coefficient 2.27 \[SD 0.31\], p<0.001), followed by pain (Coefficient 1.08 \[SD 0.13\], p<0.001) and time waited (Coefficient for 1-month additional wait 0.12 \[SD 0.02\], p<0.001). The calculated trade-off in waiting time for a 1-level change in pain (e.g., moderate to severe pain) was 9.14 months.

These results present a new method of determining comparative priority for those on primary hip arthroplasty waiting lists. Evaluation of potential implementation in clinical practice is now required.


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_6 | Pages 36 - 36
2 May 2024
Jones R Phillips J Panteli M
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Total joint arthroplasty (TJA) is one of the commonest and most successful orthopaedic procedures used for the management of end-stage arthritis. With the recent introduction of robotic-assisted joint replacement, Computed tomography (CT) has become part of required pre-operative planning.

The aim of this study is to quantify and characterise incidental CT findings, their clinical significance, and their effect on the planned joint arthroplasty.

All consecutive patients undergoing an elective TJA (total joint arthroplasty; hip or knee) were retrospectively identified, over a 4-year period (December 2019 and November 2023). Data documented and analysed included patient demographics, type of joint arthroplasty, CT findings, their clinical significance, as well as potential delays to the planned arthroplasty because of these findings and subsequent further investigation.

A total of 987 patients (female: 514 patients (52.1%)) undergoing TJA were identified (THA: 444 patients (45.0%); TKA: 400 patients (40.5%); UKA: 143 patients (14.5%)). Incidental findings within imaged areas were identified in 227 patients (23.0%). Of these findings, 74 (7.5%) were significant, requiring further investigation or management, 40 (4.1%) of which represented potential malignancy and 4 (0.4%) resulting in a new cancer diagnosis. A single patient was found to have an aneurysm requiring urgent vascular intervention. Surgery was delayed for further investigation in 4 patients (0.4%). Significant findings were more frequent in THA patients (THA: 43 (9.7%) TKA/UKA: 31 (5.7%)

Within our cohort, 74 (7.5%) patients had significant incidental findings that required further investigations or management, with 4 (0.4%) having a previously undiagnosed malignancy. We strongly advocate that all robotic arthroplasty planning CTs are reviewed and reported by a specialist, to avoid missing undiagnosed malignancies and other significant diagnoses.


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_6 | Pages 25 - 25
2 May 2024
Ajula R Mayne A Cecchi S Ebert J Edwards P Davies P Ricciardo B Annear P D'Alessandro P
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Proximal hamstring tendon avulsion from the ischial tuberosity is a significant injury, with surgical repair shown to have superior functional outcomes compared to non-surgical treatment. However, limited data exists regarding the optimal rehabilitation regime following surgical repair. The aim of this study was to investigate patient outcomes following repair of proximal hamstring tendon avulsions between a conservative (CR) versus an accelerated rehabilitation (AR) regimen.

This prospective randomized controlled trial (RCT) randomised 50 patients undergoing proximal hamstring tendon repair to either a braced, partial weight-bearing rehabilitation regime (CR=25) or an accelerated, unbraced regime, that permitted full weight-bearing as tolerated (AR=25).

Patients were evaluated pre-operatively and at 3 and 6 months post-surgery, via patient-reported outcome measures (PROMs) including the Lower Extremity Functional Scale (LEFS), Perth Hamstring Assessment Tool (PHAT) and 12-item Short Form Health Survey (SF-12). Primary analysis was per protocol and based on linear mixed models.

Both groups were matched at baseline with respect to patient characteristics. All PROMs improved (p>0.05) and, while the AR group reported a significantly better Physical Component Score for the SF-12 at 3 months (p=0.022), there were no other group differences. Peak isometric hamstrings strength and peak isokinetic quadriceps and hamstrings torque symmetry were all comparable between groups (p>0.05). Three re-injuries have been observed (CR=2, AR=1).

After proximal hamstring repair surgery, post-operative outcomes following an accelerated rehabilitation regimen demonstrate comparable outcomes to a traditionally conservative rehabilitation pathway, albeit demonstrating better early physical health-related quality of life scores, without an increased incidence of early re-injury.


Implants in total hip replacement (THR) are associated with different clinical and cost-effectiveness profiles,. We estimate the costs and outcomes for NHS patients in the year after THR associated with implant bearing materials using linked routinely collected data.

We linked NJR primary elective THR patients for osteoarthritis to HES and National PROMs. We estimated health care costs, health-related quality of life indices, and revision risks, in the year after primary and revision THRs overall. We used generalised linear models adjusting for patient and hospital characteristics and estimated 10-year cumulative probability of revision. We imputed utilities using chained equations for half the sample with missing PROMS.

We linked 577,973 elective primary THRs and 11,812 subsequent revisions. One year after primary THR, patients with the cemented THRs using cobalt chrome or stainless steel head with HCLPE liner/cup cost the NHS, on average, £13,101 (95%CI £13,080,£13,122), had an average quality-of-life score of 0.788 (95%CI 0.787,0.788), and a 10-year revision probability of 1.9% (95%CI 1.6,2.3). Compared to the reference, patients receiving a cemented THR with delta ceramic head and HCLPE liner/cup, hybrid THR with delta ceramic head and HCLPE liner/cup, and hybrid THR with alumina head and HCLPE liner/cup had lower 1-year costs (-£572 \[95% CI -£775,-£385\], -£346 \[-£501,-£192\], -£371 \[-£574,-£168\] respectively), better quality of life (0.007 \[95% CI 0.003,0.011\], 0.013 \[0.010,0.016\], 0.009 \[0.005,0.013\] respectively), and lower 10-year revision probabilities (1.4% \[1.03,2.0\], 1.5 \[1.3,1.7\], 1.6%\[1.2,2.1\] respectively).

Implant bearing materials are associated with varying mean costs and health outcomes after primary THR. Ours is the first study to derive costs and health outcomes from large, linked databases using multiple imputation methods to deal with bias. Our findings are useful for commissioning and procurement decisions and to inform a subsequent cost-effectiveness model with more granular detail on THR implant types.


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_6 | Pages 12 - 12
2 May 2024
Selim A Al-Hadithy N Diab N Ahmed A Kader KA Hegazy M Abdelazeem H Barakat A
Full Access

Lag screw cut-out is a serious complication of dynamic hip screw fixation in trochanteric hip fractures. Lag screw position is recognised as a crucial factor influencing the occurrence of lag screw cut-out. We propose a modification of the Tip Apex Distance (TAD) and hypothesize that it could enhance the reliability of predicting lag screw cut-out in these injuries.

A retrospective study of hip fracture cases was conducted from January 2018 to July 2022. A total of 109 patients were eligible for the final analysis. The modified TAD was measured in millimetres, based on the sum of the traditional TAD in the lateral view and the net value of two distances in the anteroposterior (AP) view. The first distance is from the lag screw tip to the opposite point on the femoral head along the lag screw axis, while the second distance is from that point to the femoral head apex. The first distance is a positive value, whereas the second distance is positive if the lag screw is superior and negative if it is inferior. Receiver operating characteristic (ROC) curve analysis was used to assess the reliability of various parameters for evaluating the lag screw position within the femoral head.

Factors such as reduction quality, fracture pattern according to the AO/OTA classification, TAD, Calcar-Referenced TAD, Axis Blade Angle, Parker’s ratio in the AP view, Cleveland Zone 1, and modified TAD were statistically associated with lag screw cut-out. Among the tested parameters, the novel parameter exhibited 90.1% sensitivity and 90.9% specificity for predicting lag screw cut-out at a cut-off value of 25 mm, with a p-value < 0.001.

The modified TAD demonstrated the highest reliability in predicting lag screw cut-out. A value of 25 mm may potentially reduce the risk of lag screw cut-out in trochanteric hip fractures.


Bone & Joint Open
Vol. 4, Issue 3 | Pages 154 - 161
28 Mar 2023
Homma Y Zhuang X Watari T Hayashi K Baba T Kamath A Ishijima M

Aims

It is important to analyze objectively the hammering sound in cup press-fit technique in total hip arthroplasty (THA) in order to better understand the change of the sound during impaction. We hypothesized that a specific characteristic would present in a hammering sound with successful fixation. We designed the study to quantitatively investigate the acoustic characteristics during cementless cup impaction in THA.

Methods

In 52 THAs performed between November 2018 and April 2022, the acoustic parameters of the hammering sound of 224 impacts of successful press-fit fixation, and 55 impacts of unsuccessful press-fit fixation, were analyzed. The successful fixation was defined if the following two criteria were met: 1) intraoperatively, the stability of the cup was retained after manual application of the torque test; and 2) at one month postoperatively, the cup showed no translation on radiograph. Each hammering sound was converted to sound pressures in 24 frequency bands by fast Fourier transform analysis. Basic patient characteristics were assessed as potential contributors to the hammering sound.


Bone & Joint Open
Vol. 3, Issue 11 | Pages 859 - 866
4 Nov 2022
Diesel CV Guimarães MR Menegotto SM Pereira AH Pereira AA Bertolucci LH Freitas EC Galia CR

Aims

Our objective was describing an algorithm to identify and prevent vascular injury in patients with intrapelvic components.

Methods

Patients were defined as at risk to vascular injuries when components or cement migrated 5 mm or more beyond the ilioischial line in any of the pelvic incidences (anteroposterior and Judet view). In those patients, a serial investigation was initiated by a CT angiography, followed by a vascular surgeon evaluation. The investigation proceeded if necessary. The main goal was to assure a safe tissue plane between the hardware and the vessels.


Bone & Joint Open
Vol. 5, Issue 4 | Pages 286 - 293
9 Apr 2024
Upadhyay PK Kumar V Mirza SB Shah N

Aims

This study reports the results of 38 total hip arthroplasties (THAs) in 33 patients aged less than 50 years, using the JRI Furlong hydroxyapatite ceramic (HAC)-coated femoral component.

Methods

We describe the survival, radiological, and functional outcomes of 33 patients (38 THAs) at a mean follow-up of 27 years (25 to 32) between 1988 and 2018.


Bone & Joint Open
Vol. 5, Issue 4 | Pages 304 - 311
15 Apr 2024
Galloway R Monnington K Moss R Donaldson J Skinner J McCulloch R

Aims

Young adults undergoing total hip arthroplasty (THA) largely have different indications for surgery, preoperative function, and postoperative goals compared to a standard patient group. The aim of our study was to describe young adult THA preoperative function and quality of life, and to assess postoperative satisfaction and compare this with functional outcome measures.

Methods

A retrospective cohort analysis of young adults (aged < 50 years) undergoing THA between May 2018 and May 2023 in a single tertiary centre was undertaken. Median follow-up was 31 months (12 to 61). Oxford Hip Score (OHS) and focus group-designed questionnaires were distributed. Searches identified 244 cases in 225 patients. Those aged aged under 30 years represented 22.7% of the cohort. Developmental dysplasia of the hip (50; 45.5%) and Perthes’ disease (15; 13.6%) were the commonest indications for THA.


Bone & Joint Open
Vol. 4, Issue 5 | Pages 385 - 392
24 May 2023
Turgeon TR Hedden DR Bohm ER Burnell CD

Aims

Instability is a common cause of failure after total hip arthroplasty. A novel reverse total hip has been developed, with a femoral cup and acetabular ball, creating enhanced mechanical stability. The purpose of this study was to assess the implant fixation using radiostereometric analysis (RSA), and the clinical safety and efficacy of this novel design.

Methods

Patients with end-stage osteoarthritis were enrolled in a prospective cohort at a single centre. The cohort consisted of 11 females and 11 males with mean age of 70.6 years (SD 3.5) and BMI of 31.0 kg/m2 (SD 5.7). Implant fixation was evaluated using RSA as well as Western Ontario and McMaster Universities Osteoarthritis Index, Harris Hip Score, Oxford Hip Score, Hip disability and Osteoarthritis Outcome Score, 38-item Short Form survey, and EuroQol five-dimension health questionnaire scores at two-year follow-up. At least one acetabular screw was used in all cases. RSA markers were inserted into the innominate bone and proximal femur with imaging at six weeks (baseline) and six, 12, and 24 months. Independent-samples t-tests were used to compare to published thresholds.


Bone & Joint Open
Vol. 4, Issue 3 | Pages 182 - 187
14 Mar 2023
Sheridan GA Hanlon M Welch-Phillips A Spratt K Hagan R O'Byrne JM Kenny PJ Kurmis AP Masri BA Garbuz DS Hurson CJ

Aims

Hip resurfacing remains a potentially valuable surgical procedure for appropriately-selected patients with optimised implant choices. However, concern regarding high early failure rates continues to undermine confidence in use. A large contributor to failure is adverse local tissue reactions around metal-on-metal (MoM) bearing surfaces. Such phenomena have been well-explored around MoM total hip arthroplasties, but comparable data in equivalent hip resurfacing procedures is lacking. In order to define genetic predisposition, we performed a case-control study investigating the role of human leucocyte antigen (HLA) genotype in the development of pseudotumours around MoM hip resurfacings.

Methods

A matched case-control study was performed using the prospectively-collected database at the host institution. In all, 16 MoM hip resurfacing 'cases' were identified as having symptomatic periprosthetic pseudotumours on preoperative metal artefact reduction sequence (MARS) MRI, and were subsequently histologically confirmed as high-grade aseptic lymphocyte-dominated vasculitis-associated lesions (ALVALs) at revision surgery. ‘Controls’ were matched by implant type in the absence of evidence of pseudotumour. Blood samples from all cases and controls were collected prospectively for high resolution genetic a nalysis targeting 11 separate HLA loci. Statistical significance was set at 0.10 a priori to determine the association between HLA genotype and pseudotumour formation, given the small sample size.


Bone & Joint Open
Vol. 4, Issue 10 | Pages 766 - 775
13 Oct 2023
Xiang L Singh M McNicoll L Moppett IK

Aims

To identify factors influencing clinicians’ decisions to undertake a nonoperative hip fracture management approach among older people, and to determine whether there is global heterogeneity regarding these factors between clinicians from high-income countries (HIC) and low- and middle-income countries (LMIC).

Methods

A SurveyMonkey questionnaire was electronically distributed to clinicians around the world through the Fragility Fracture Network (FFN)’s Perioperative Special Interest Group and clinicians’ personal networks between 24 May and 25 July 2021. Analyses were performed using Excel and STATA v16.0. Between-group differences were determined using independent-samples t-tests and chi-squared tests.


Bone & Joint Open
Vol. 4, Issue 6 | Pages 408 - 415
1 Jun 2023
Ramkumar PN Shaikh HJF Woo JJ Haeberle HS Pang M Brooks PJ

Aims

The aims of the study were to report for a cohort aged younger than 40 years: 1) indications for HRA; 2) patient-reported outcomes in terms of the modified Harris Hip Score (HHS); 3) dislocation rate; and 4) revision rate.

Methods

This retrospective analysis identified 267 hips from 224 patients who underwent an hip resurfacing arthroplasty (HRA) from a single fellowship-trained surgeon using the direct lateral approach between 2007 and 2019. Inclusion criteria was minimum two-year follow-up, and age younger than 40 years. Patients were followed using a prospectively maintained institutional database.


Bone & Joint Open
Vol. 5, Issue 3 | Pages 174 - 183
6 Mar 2024
Omran K Waren D Schwarzkopf R

Aims

Total hip arthroplasty (THA) is a common procedure to address pain and enhance function in hip disorders such as osteoarthritis. Despite its success, postoperative patient recovery exhibits considerable heterogeneity. This study aimed to investigate whether patients follow distinct pain trajectories following THA and identify the patient characteristics linked to suboptimal trajectories.

Methods

This retrospective cohort study analyzed THA patients at a large academic centre (NYU Langone Orthopedic Hospital, New York, USA) from January 2018 to January 2023, who completed the Patient-Reported Outcomes Measurement Information System (PROMIS) pain intensity questionnaires, collected preoperatively at one-, three-, six-, 12-, and 24-month follow-up times. Growth mixture modelling (GMM) was used to model the trajectories. Optimal model fit was determined by Bayesian information criterion (BIC), Vuong-Lo-Mendell-Rubin likelihood ratio test (VLMR-LRT), posterior probabilities, and entropy values. Association between trajectory groups and patient characteristics were measured by multinomial logistic regression using the three-step approach.


The Bone & Joint Journal
Vol. 105-B, Issue 10 | Pages 1060 - 1069
1 Oct 2023
Holleyman RJ Jameson SS Reed M Meek RMD Khanduja V Hamer A Judge A Board T

Aims

This study describes the variation in the annual volumes of revision hip arthroplasty (RHA) undertaken by consultant surgeons nationally, and the rate of accrual of RHA and corresponding primary hip arthroplasty (PHA) volume for new consultants entering practice.

Methods

National Joint Registry (NJR) data for England, Wales, Northern Ireland, and the Isle of Man were received for 84,816 RHAs and 818,979 PHAs recorded between April 2011 and December 2019. RHA data comprised all revision procedures, including first-time revisions of PHA and any subsequent re-revisions recorded in public and private healthcare organizations. Annual procedure volumes undertaken by the responsible consultant surgeon in the 12 months prior to every index procedure were determined. We identified a cohort of ‘new’ HA consultants who commenced practice from 2012 and describe their rate of accrual of PHA and RHA experience.


Bone & Joint Open
Vol. 4, Issue 5 | Pages 370 - 377
19 May 2023
Comeau-Gauthier M Bzovsky S Axelrod D Poolman RW Frihagen F Bhandari M Schemitsch E Sprague S

Aims

Using data from the Hip Fracture Evaluation with Alternatives of Total Hip Arthroplasty versus Hemiarthroplasty (HEALTH) trial, we sought to determine if a difference in functional outcomes exists between monopolar and bipolar hemiarthroplasty (HA).

Methods

This study is a secondary analysis of patients aged 50 years or older with a displaced femoral neck fracture who were enrolled in the HEALTH trial and underwent monopolar and bipolar HA. Scores from the Western Ontario and McMaster University Arthritis Index (WOMAC) and 12-Item Short Form Health Survey (SF-12) Physical Component Summary (PCS) and (MCS) were compared between the two HA groups using a propensity score-weighted analysis.


Bone & Joint Open
Vol. 4, Issue 12 | Pages 932 - 941
6 Dec 2023
Oe K Iida H Otsuki Y Kobayashi F Sogawa S Nakamura T Saito T

Aims

Although there are various pelvic osteotomies for acetabular dysplasia of the hip, shelf operations offer effective and minimally invasive osteotomy. Our study aimed to assess outcomes following modified Spitzy shelf acetabuloplasty.

Methods

Between November 2000 and December 2016, we retrospectively evaluated 144 consecutive hip procedures in 122 patients a minimum of five years after undergoing modified Spitzy shelf acetabuloplasty for acetabular dysplasia including osteoarthritis (OA). Our follow-up rate was 92%. The mean age at time of surgery was 37 years (13 to 58), with a mean follow-up of 11 years (5 to 21). Advanced OA (Tönnis grade ≥ 2) was present preoperatively in 16 hips (11%). The preoperative lateral centre-edge angle ranged from -28° to 25°. Survival was determined by Kaplan-Meier analysis, using conversions to total hip arthroplasty as the endpoint. Risk factors for joint space narrowing less than 2 mm were analyzed using a Cox proportional hazards model.


Bone & Joint Open
Vol. 4, Issue 9 | Pages 668 - 675
3 Sep 2023
Aubert T Gerard P Auberger G Rigoulot G Riouallon G

Aims

The risk factors for abnormal spinopelvic mobility (SPM), defined as an anterior rotation of the spinopelvic tilt (∆SPT) ≥ 20° in a flexed-seated position, have been described. The implication of pelvic incidence (PI) is unclear, and the concept of lumbar lordosis (LL) based on anatomical limits may be erroneous. The distribution of LL, including a unusual shape in patients with a high lordosis, a low pelvic incidence, and an anteverted pelvis seems more relevant.

Methods

The clinical data of 311 consecutive patients who underwent total hip arthroplasty was retrospectively analyzed. We analyzed the different types of lumbar shapes that can present in patients to identify their potential associations with abnormal pelvic mobility, and we analyzed the potential risk factors associated with a ∆SPT ≥ 20° in the overall population.


The Bone & Joint Journal
Vol. 105-B, Issue 2 | Pages 140 - 147
1 Feb 2023
Fu Z Zhang Z Deng S Yang J Li B Zhang H Liu J

Aims

Eccentric reductions may become concentric through femoral head ‘docking’ (FHD) following closed reduction (CR) for developmental dysplasia of the hip (DDH). However, changes regarding position and morphology through FHD are not well understood. We aimed to assess these changes using serial MRI.

Methods

We reviewed 103 patients with DDH successfully treated by CR and spica casting in a single institution between January 2016 and December 2020. MRI was routinely performed immediately after CR and at the end of each cast. Using MRI, we described the labrum-acetabular cartilage complex (LACC) morphology, and measured the femoral head to triradiate cartilage distance (FTD) on the midcoronal section. A total of 13 hips with initial complete reduction (i.e. FTD < 1 mm) and ten hips with incomplete MRI follow-up were excluded. A total of 86 patients (92 hips) with a FTD > 1 mm were included in the analysis.


Bone & Joint Open
Vol. 5, Issue 4 | Pages 260 - 268
1 Apr 2024
Broekhuis D Meurs WMH Kaptein BL Karunaratne S Carey Smith RL Sommerville S Boyle R Nelissen RGHH

Aims

Custom triflange acetabular components (CTACs) play an important role in reconstructive orthopaedic surgery, particularly in revision total hip arthroplasty (rTHA) and pelvic tumour resection procedures. Accurate CTAC positioning is essential to successful surgical outcomes. While prior studies have explored CTAC positioning in rTHA, research focusing on tumour cases and implant flange positioning precision remains limited. Additionally, the impact of intraoperative navigation on positioning accuracy warrants further investigation. This study assesses CTAC positioning accuracy in tumour resection and rTHA cases, focusing on the differences between preoperative planning and postoperative implant positions.

Methods

A multicentre observational cohort study in Australia between February 2017 and March 2021 included consecutive patients undergoing acetabular reconstruction with CTACs in rTHA (Paprosky 3A/3B defects) or tumour resection (including Enneking P2 peri-acetabular area). Of 103 eligible patients (104 hips), 34 patients (35 hips) were analyzed.


The Bone & Joint Journal
Vol. 104-B, Issue 7 | Pages 811 - 819
1 Jul 2022
Galvain T Mantel J Kakade O Board TN

Aims

The aim of this study was to estimate the clinical and economic burden of dislocation following primary total hip arthroplasty (THA) in England.

Methods

This retrospective evaluation used data from the UK Clinical Practice Research Datalink database. Patients were eligible if they underwent a primary THA (index date) and had medical records available 90 days pre-index and 180 days post-index. Bilateral THAs were excluded. Healthcare costs and resource use were evaluated over two years. Changes (pre- vs post-THA) in generic quality of life (QoL) and joint-specific disability were evaluated. Propensity score matching controlled for baseline differences between patients with and without THA dislocation.


The Bone & Joint Journal
Vol. 104-B, Issue 7 | Pages 775 - 780
1 Jul 2022
Kołodziejczyk K Czubak-Wrzosek M Kwiatkowska M Czubak J

Aims

Developmental dysplasia of the hip (DDH) describes a pathological relationship between the femoral head and acetabulum. Periacetabular osteotomy (PAO) may be used to treat this condition. The aim of this study was to evaluate the results of PAO in adolescents and adults with persistent DDH.

Methods

Patients were divided into four groups: A, adolescents who had not undergone surgery for DDH in childhood (25 hips); B, adolescents who had undergone surgery for DDH in childhood (20 hips); C, adults with DDH who had not undergone previous surgery (80 hips); and D, a control group of patients with healthy hips (70 hips). The radiological evaluation of digital anteroposterior views of hips included the Wiberg angle (centre-edge angle (CEA)), femoral head cover (FHC), medialization, distalization, and the ilioischial angle. Clinical assessment involved the Harris Hip Score (HHS) and gluteal muscle performance assessment.


Bone & Joint Open
Vol. 3, Issue 6 | Pages 485 - 494
13 Jun 2022
Jaubert M Le Baron M Jacquet C Couvreur A Fabre-Aubrespy M Flecher X Ollivier M Argenson J

Aims

Two-stage exchange revision total hip arthroplasty (THA) performed in case of periprosthetic joint infection (PJI) has been considered for many years as being the gold standard for the treatment of chronic infection. However, over the past decade, there have been concerns about its safety and its effectiveness. The purposes of our study were to investigate our practice, collecting the overall spacer complications, and then to analyze their risk factors.

Methods

We retrospectively included 125 patients with chronic hip PJI who underwent a staged THA revision performed between January 2013 and December 2019. All spacer complications were systematically collected, and risk factors were analyzed. Statistical evaluations were performed using the Student's t-test, Mann-Whitney U test, and Fisher's exact test.


Bone & Joint Open
Vol. 3, Issue 6 | Pages 475 - 484
13 Jun 2022
Jang SJ Vigdorchik JM Windsor EW Schwarzkopf R Mayman DJ Sculco PK

Aims

Navigation devices are designed to improve a surgeon’s accuracy in positioning the acetabular and femoral components in total hip arthroplasty (THA). The purpose of this study was to both evaluate the accuracy of an optical computer-assisted surgery (CAS) navigation system and determine whether preoperative spinopelvic mobility (categorized as hypermobile, normal, or stiff) increased the risk of acetabular component placement error.

Methods

A total of 356 patients undergoing primary THA were prospectively enrolled from November 2016 to March 2018. Clinically relevant error using the CAS system was defined as a difference of > 5° between CAS and 3D radiological reconstruction measurements for acetabular component inclination and anteversion. Univariate and multiple logistic regression analyses were conducted to determine whether hypermobile (Δsacral slope(SS)stand-sit > 30°), or stiff (SSstand-sit < 10°) spinopelvic mobility contributed to increased error rates.


Bone & Joint Research
Vol. 11, Issue 5 | Pages 317 - 326
23 May 2022
Edwards TC Guest B Garner A Logishetty K Liddle AD Cobb JP

Aims

This study investigates the use of the metabolic equivalent of task (MET) score in a young hip arthroplasty population, and its ability to capture additional benefit beyond the ceiling effect of conventional patient-reported outcome measures.

Methods

From our electronic database of 751 hip arthroplasty procedures, 221 patients were included. Patients were excluded if they had revision surgery, an alternative hip procedure, or incomplete data either preoperatively or at one-year follow-up. Included patients had a mean age of 59.4 years (SD 11.3) and 54.3% were male, incorporating 117 primary total hip and 104 hip resurfacing arthroplasty operations. Oxford Hip Score (OHS), EuroQol five-dimension questionnaire (EQ-5D), and the MET were recorded preoperatively and at one-year follow-up. The distribution was examined reporting the presence of ceiling and floor effects. Validity was assessed correlating the MET with the other scores using Spearman’s rank correlation coefficient and determining responsiveness. A subgroup of 93 patients scoring 48/48 on the OHS were analyzed by age, sex, BMI, and preoperative MET using the other metrics to determine if differences could be established despite scoring identically on the OHS.


Bone & Joint Open
Vol. 3, Issue 5 | Pages 404 - 414
9 May 2022
McGuire MF Vakulenko-Lagun B Millis MB Almakias R Cole EP Kim HKW

Aims

Perthes’ disease is an uncommon hip disorder with limited data on the long-term outcomes in adulthood. We partnered with community-based foundations and utilized web-based survey methodology to develop the Adult Perthes Survey, which includes demographics, childhood and adult Perthes’ disease history, the University of California Los Angeles (UCLA) Activity Scale item, Short Form-36, the Hip disability and Osteoarthritis Outcome Score, and a body pain diagram. Here we investigate the following questions: 1) what is the feasibility of obtaining > 1,000 survey responses from adults who had Perthes’ disease using a web-based platform?; and 2) what are the baseline characteristics and demographic composition of our sample?

Methods

The survey link was available publicly for 15 months and advertised among support groups. Of 1,505 participants who attempted the Adult Perthes survey, 1,182 completed it with a median timeframe of 11 minutes (IQR 8.633 to 14.72). Participants who dropped out were similar to those who completed the survey on several fixed variables. Participants represented 45 countries including the USA (n = 570; 48%), UK (n = 295; 25%), Australia (n = 133; 11%), and Canada (n = 46; 4%). Of the 1,182 respondents, 58% were female and the mean age was 39 years (SD 12.6).


Bone & Joint Research
Vol. 11, Issue 5 | Pages 270 - 277
6 May 2022
Takegami Y Seki T Osawa Y Imagama S

Aims

Periprosthetic hip fractures (PPFs) after total hip arthroplasty are difficult to treat. Therefore, it is important to identify modifiable risk factors such as stem selection to reduce the occurrence of PPFs. This study aimed to clarify differences in fracture torque, surface strain, and fracture type analysis between three different types of cemented stems.

Methods

We conducted biomechanical testing of bone analogues using six cemented stems of three different types: collarless polished tapered (CPT) stem, Versys Advocate (Versys) stem, and Charnley-Marcel-Kerboull (CMK) stem. Experienced surgeons implanted each of these types of stems into six bone analogues, and the analogues were compressed and internally rotated until failure. Torque to fracture and fracture type were recorded. We also measured surface strain distribution using triaxial rosettes.


Bone & Joint Open
Vol. 3, Issue 5 | Pages 423 - 431
1 May 2022
Leong JWY Singhal R Whitehouse MR Howell JR Hamer A Khanduja V Board TN

Aims

The aim of this modified Delphi process was to create a structured Revision Hip Complexity Classification (RHCC) which can be used as a tool to help direct multidisciplinary team (MDT) discussions of complex cases in local or regional revision networks.

Methods

The RHCC was developed with the help of a steering group and an invitation through the British Hip Society (BHS) to members to apply, forming an expert panel of 35. We ran a mixed-method modified Delphi process (three rounds of questionnaires and one virtual meeting). Round 1 consisted of identifying the factors that govern the decision-making and complexities, with weighting given to factors considered most important by experts. Participants were asked to identify classification systems where relevant. Rounds 2 and 3 focused on grouping each factor into H1, H2, or H3, creating a hierarchy of complexity. This was followed by a virtual meeting in an attempt to achieve consensus on the factors which had not achieved consensus in preceding rounds.


Bone & Joint Open
Vol. 3, Issue 4 | Pages 340 - 347
22 Apr 2022
Winkler T Costa ML Ofir R Parolini O Geissler S Volk H Eder C

Aims

The aim of the HIPGEN consortium is to develop the first cell therapy product for hip fracture patients using PLacental-eXpanded (PLX-PAD) stromal cells.

Methods

HIPGEN is a multicentre, multinational, randomized, double-blind, placebo-controlled trial. A total of 240 patients aged 60 to 90 years with low-energy femoral neck fractures (FNF) will be allocated to two arms and receive an intramuscular injection of either 150 × 106 PLX-PAD cells or placebo into the medial gluteal muscle after direct lateral implantation of total or hemi hip arthroplasty. Patients will be followed for two years. The primary endpoint is the Short Physical Performance Battery (SPPB) at week 26. Secondary and exploratory endpoints include morphological parameters (lean body mass), functional parameters (abduction and handgrip strength, symmetry in gait, weightbearing), all-cause mortality rate and patient-reported outcome measures (Lower Limb Measure, EuroQol five-dimension questionnaire). Immunological biomarker and in vitro studies will be performed to analyze the PLX-PAD mechanism of action. A sample size of 240 subjects was calculated providing 88% power for the detection of a 1 SPPB point treatment effect for a two-sided test with an α level of 5%.


Bone & Joint Open
Vol. 3, Issue 4 | Pages 332 - 339
20 Apr 2022
Everett BP Sherrill G Nakonezny PA Wells JE

Aims

This study aims to answer the following questions in patients with hip osteoarthritis (OA) who underwent total hip arthroplasty (THA): are patient-reported outcome measures (PROMs) affected by the location of the maximum severity of pain?; are PROMs affected by the presence of non-groin pain?; are PROMs affected by the severity of pain?; and are PROMs affected by the number of pain locations?

Methods

We reviewed 336 hips (305 patients) treated with THA for hip OA from December 2016 to November 2019 using pain location/severity questionnaires, modified Harris Hip Score (mHHS), Hip Outcome Score (HOS), international Hip Outcome Tool (iHOT-12) score, and radiological analysis. Descriptive statistics, analysis of covariance (ANCOVA), and Spearman partial correlation coefficients were used.


Bone & Joint Open
Vol. 3, Issue 4 | Pages 314 - 320
7 Apr 2022
Malhotra R Batra S Sugumar PA Gautam D

Aims

Adult patients with history of childhood infection pose a surgical challenge for total hip arthroplasty (THA) due to distorted bony anatomy, soft-tissue contractures, risk of reinfection, and relatively younger age. Therefore, the purpose of the present study was to determine clinical outcome, reinfection rate, and complications in patients with septic sequelae after THA.

Methods

A retrospective analysis was conducted of 91 cementless THAs (57 male and 34 female) performed between 2008 and 2017 in patients who had history of hip infection during childhood. Clinical outcome was measured using Harris Hip Score (HHS) and Modified Merle d’Aubigne and Postel (MAP) score, and quality of life (QOL) using 12-Item Short Form Health Survey Questionnaire (SF-12) components: Physical Component Score (PCS) and Mental Component Score (MCS); limb length discrepancy (LLD) and radiological assessment of the prosthesis was performed at the latest follow-up. Reinfection and revision surgery after THA for any reason was documented.


Bone & Joint Open
Vol. 3, Issue 4 | Pages 307 - 313
7 Apr 2022
Singh V Bieganowski T Huang S Karia R Davidovitch RI Schwarzkopf R

Aims

The Forgotten Joint Score-12 (FJS-12) is a validated patient-reported outcome measure (PROM) tool designed to assess artificial prosthesis awareness during daily activities following total hip arthroplasty (THA). The patient-acceptable symptom state (PASS) is the minimum cut-off value that corresponds to a patient’s satisfactory state-of-health. Despite the validity and reliability of the FJS-12 having been previously demonstrated, the PASS has yet to be clearly defined. This study aims to define the PASS of the FJS-12 following primary THA.

Methods

We retrospectively reviewed all patients who underwent primary elective THA from 2019 to 2020, and answered both the FJS-12 and the Hip Disability and Osteoarthritis Outcome Score, Joint Replacement (HOOS, JR) questionnaires one-year postoperatively. HOOS, JR score was used as the anchor to estimate the PASS of FJS-12. Two statistical methods were employed: the receiver operating characteristic (ROC) curve point, which maximized the Youden index; and 75th percentile of the cumulative percentage curve of patients who had the HOOS, JR score difference larger than the cut-off value.


Bone & Joint Open
Vol. 3, Issue 4 | Pages 291 - 301
4 Apr 2022
Holleyman RJ Lyman S Bankes MJK Board TN Conroy JL McBryde CW Andrade AJ Malviya A Khanduja V

Aims

This study uses prospective registry data to compare early patient outcomes following arthroscopic repair or debridement of the acetabular labrum.

Methods

Data on adult patients who underwent arthroscopic labral debridement or repair between 1 January 2012 and 31 July 2019 were extracted from the UK Non-Arthroplasty Hip Registry. Patients who underwent microfracture, osteophyte excision, or a concurrent extra-articular procedure were excluded. The EuroQol five-dimension (EQ-5D) and International Hip Outcome Tool 12 (iHOT-12) questionnaires were collected preoperatively and at six and 12 months post-operatively. Due to concerns over differential questionnaire non-response between the two groups, a combination of random sampling, propensity score matching, and pooled multivariable linear regression models were employed to compare iHOT-12 improvement.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_4 | Pages 3 - 3
1 Apr 2022
Jain S Menon D Sheikh S Bennett D Mitchell T Kerr J Bassi V Pandit H
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Periprosthetic femoral fracture (PFF) incidence following hip replacement surgery continues to rise. There is a national drive to centralise PFF treatment within specialist centres to improve clinical outcomes and cost-effectiveness. The financial implications of treating PFFs must be analysed to guide allocation of funding.

Data were collected for 129 PFFs admitted from 02/04/2014–19/05/2020. Financial data were provided by the Patient Level Information and Costing Systems (PLICS) team. Primary outcomes were cost, revenue and margin for each PFF. Additional data were collected on length of stay (LOS), critical care requirements and clinical outcomes. Statistical comparisons were made between treatment type (fixation vs revision). Significance was set to p<0.05.

Across the entire cohort, total cost was £2,389,901, total revenue was £1,695,435 and total loss was £694,481. Highest costs were ward stay (£714,591), theatre utilisation (£382,625), and overheads (£249,110). Median cost was £15,863 (IQR, £11,092-£22,221), median revenue was £11,305 (IQR, £7,147-£15,222) and median loss was £3,795 (IQR, £605-£8687). Median LOS was 21 days (IQR 13–34) and 28.7% patients required critical care admission.

Ninety-six patients were treated operatively with either fixation (n=53) or revision (n=43). Median operating time was lower for fixation versus revision (132 [IQR, 115–185] vs 201 [IQR, 159–229] minutes, p=0.001). Median cost (£17,455 [IQR, £13,095-£22,824] vs £17,399 [£13,394-£23,404]) and median loss (£5,774 [IQR, £2,092-£10,472] vs £3,860 [IQR, £96-£7,601]) were similar for fixation and revision (p=0.99 and p=0.18, respectively). Median revenue was greater for revision versus fixation (£13,925 [IQR, £11,294-£17,037] vs £12,160 [IQR, £8,486-£14,390], p=0.02). There was no difference in LOS (21 [13–34] vs 21 [14–30] days, p=0.94), critical care requirements (20 [37.7%] vs 11 [25.6%], p=0.30), reoperations (3 [5.7%] vs 6 [14.0%], p=0.29], local complications (8 [15.1%) vs 12 [27.9%], p=0.20) or systemic complications (11 [20.8%] vs 11 [25.6%], p=0.75) between fixation and revision.

PFF treatment costs are high with inadequate reimbursement through tariff. Work is needed to address this disparity and reduce costs associated with LOS, theatre utilisation and implants. Treatment cost should not be used when deciding between fixation and revision surgery.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_4 | Pages 37 - 37
1 Apr 2022
Holleyman R Kumar KS Khanduja V Malviya A
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Young adult hip pathology commonly affects patients of reproductive age. The extent to which hip arthroscopy (HA) treatments influence sexual function is not well described and limited to small cohorts. This study aims to describe trends in self-reported reported sexual function before and after HA.

Adult (≥18 years) patients who underwent HA between 1st January 2012 and 31st October 2020 were extracted from the UK Non-Arthroplasty Hip Registry. International Hip Outcome Tool 12 (iHOT-12) questionnaires were collected pre-operatively and at 6 and 12 months. Patients are first asked if ‘questions about sexual activity are relevant to them’. The iHOT-12 then asks asking patients to quantify ‘how much trouble they experience with sexual activity because of their hip?’ with responses converted to a continuous scale (0–100) to measure function. Chi-squared and t-tests were used to compare categorical and continuous variables respectively.

Of 7639 procedures (59% female, mean age 36.5 years (SD 11)), 91% (5616 of 6151 respondants) indicated pre-operatively that questions about sexual activity were relevant to them (male 93%, female 90%, p < 0.001). Overall, mean pre-operative sexual function increased from 42.0 (95%CI 41.2 to 42.8, n=5267) to 61.8 (60.6 to 63.1, n=2393) at 6 months, and 62.1 (60.8 to 63.5, n=2246) at 12 months post-operatively.

At 12 months, both sexes saw significant improvement in their pre-operative sexual function scores (p<0.0001). Males started from significantly higher baseline sexual function (53.3 vs 34.2) and achieved higher scores by 12 months (68.8 vs 58.0) compared to female patients. There was no significant difference in pre- or post-operative scores when comparing younger (<40 years) and older (>40 years).

Most patients can expect to experience improvement in their sexual function following hip arthroscopy, regardless of sex or age group.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_4 | Pages 6 - 6
1 Apr 2022
Mayne A Cassidy R Magill P Mockford B Acton D McAlinden G
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Waiting times for arthroplasty surgery in Northern Ireland are among the longest in the National Health Service, which have been further lengthened by the onset of the SARS-CoV-19 global pandemic in March 2020. The Department of Health (DoH) in Northern Ireland has announced a new Elective Care Framework (ECF), with the framework proposing that by March 2026 no patient will wait more than 52 weeks for inpatient/day case treatment. We aimed to assess the feasibility of achieving this with reference to Total Hip Arthroplasty (THA).

Waiting list information was obtained via a Freedom of Information request to the DoH (May 2021) and National Joint Registry data was used to determine baseline operative numbers. Mathematical modelling was undertaken to calculate the time taken to meet the ECF target and also to determine the time to clear the waiting lists for THA using the number of patients currently on the waiting list and percentage operating capacity relative to pre-Covid-19 capacity to determine future projections.

As of May 2021, there were 3,757 patients awaiting primary THA in Northern Ireland. Prior to April 2020, there were a mean 2,346 patients/annum added to the waiting list for primary THA and there were a mean 1,624 primary THAs performed per annum.

The ECF targets for THA will only be achieved in 2026 if operating capacity is 200% of pre COVID-19 pandemic capacity and will be achieved in 2030 if capacity is 170%. Surgical capacity must exceed pre-Covid capacity by at least 30% to meet ongoing demand.

THA capacity was significantly reduced following resumption of elective orthopaedics post-COVID-19 (22% of pre-COVID-19 capacity – 355 THAs/annum post-COVID-19 versus 1,624/annum pre-COVID-19).

This modelling demonstrates that, in the absence of major funding and reorganisation of elective orthopaedic care, the targets set out in the ECF will not be achieved with regards to hip arthroplasty. Waiting times for THA surgery in the NHS in Northern Ireland are likely to remain greater than 52 weeks for most of this decade.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_4 | Pages 7 - 7
1 Apr 2022
Afzal I Field R
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Disease specific or generic Patient Reported Outcome Measures (PROMs) can be completed by patients using paper and postal services (pPROMS) or via computer, tablet or smartphone (ePROMs) or by hybrid data collection, which uses both paper and electronic questionnaires. We have investigated whether there are differences in scores depending on the method of PROMs acquisition for the Oxford Hip Score (OHS) and the EQ-5D scores, at one and two years post operatively.

Patients for this study were identified retrospectively from a prospectively compiled arthroplasty database held at the study centre. Patient demographics, mode of preferred data collection and pre- and post-operative PROMs for Total Hip Replacements (THRs) performed at this centre between 1st January 2018 and 31st December 2018 were collected.

During the study period, 1494 patients underwent THRs and had complete one and two-year PROMs data available for analysis. All pre-operative scores were obtained by pPROMS. The average OHS and EQ-5D pre-operatively scores were 19.51 and 0.36 respectively. 72.02% of the patients consented to undertake post-operative questionnaires using ePROMs. The remaining 27.98% opted for pPROMS. The one and two-year OHS for ePROMS patients increased to 41.31 and 42.14 while the OHS scores for pPROMS patients were 39.80 and 39.83. At the one and two-year post-operative time intervals, a Mann-Whitney test showed statistical significance between the modes of administration for OHS (P-Value =0.044 and 0.01 respectively). The one and two-year EQ-5D for ePROMS patients increased to 0.83 and 0.84 while the EQ-5D scores for pPROMS patients were 0.79 and 0.81. The P-Value for Mann-Whitney tests comparing the modes of administration for EQ-5D were 0.13 and 0.07 respectively.

Within Orthopaedics, PROMs have become the most widely used instrument to assess patients’ subjective outcomes. However, there is no agreed mode of PROMs data acquisition. While we have demonstrated an apparent difference in scores depending on the mode of administration, further work is required to establish the influence of potentially confounding factors such as patient age, gender and familiarity with computer technology.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_4 | Pages 12 - 12
1 Apr 2022
Walton T Huntley D Whitehouse S Ross A Kassam A
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The aim of this study was to systemically review the evidence for the use of intra-operative cell salvage (ICS) among patients undergoing revision hip arthroplasty, and synthesis the available data to quantify any associated reduction in allogeneic blood transfusion.

An electronic database search of MEDLINE (PubMed), EMBASE, Scopus and the Cochrane Library was completed from the date of inception to 9th February 2021, using a search strategy and protocol created in conjunction with the PRISMA statement. Inclusion criteria were (i) adult patients >18 years, (ii) ICS utilised in one study group, (iii) revision hip arthroplasty performed. Exclusion criteria were (i) pre-donation of red blood cells, (ii) mixed reporting without dedicated subgroup analysis for revision hip arthroplasty. Screening for eligibility, and quality assessment of included studies, was performed independently by two authors (TW and DH), and any disputes settled by third author (AK).

Of the 187 records identified, 11 studies were included in the qualitative analysis, and 5 studies suitable for quantitative meta-analysis. Across the included studies there were 1856 participants, with a mean age of 63.86 years and a male: female ratio of 0.90. Quality assessment demonstrated low or medium risk of bias only. For revision hip arthroplasty patients receiving ICS, 37.07% required ABT with a mean transfusion of 1.92 units or 385ml per patient. For patients treated without ICS, 64.58% required ABT with a mean transfusion of 4.02 units or 803ml per patient. This difference achieved statistical significance (p < 0.05).

This study has demonstrated a significant reduction in the need for allogenic blood transfusion associated with intra-operative cell salvage use among patients undergoing revision hip arthroplasty. This study therefore supports the routine use of ICS in this patient group. However, a major limitation is the lack of clinical outcomes reported by the available studies. Further research is required to determine whether this effect is associated with sub-groups of revision arthroplasty procedure, and whether ICS impacts clinical outcomes such as length of stay, rehabilitation progress and mortality.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_4 | Pages 38 - 38
1 Apr 2022
Plastow R Kayani B Paton B Moriarty P Wilson M Court N Giakoumis M Read P Kerkhoffs G Moore J Murphy S Pollock N Stirling B Tulloch L Van Dyk N Wood D Haddad FS
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The 2020 London International Hamstring Consensus meeting was convened to improve our understanding and treatment of hamstring injuries.

The multidisciplinary consensus panel included 14 International specialists on the management of hamstring injuries. The Delphi consensus process consisted of two rounds of surveys which were completed by 19 surgeons from a total of 106 participants. Consensus on individual statements was regarded as over 70% agreement between panel members.

The consensus group agreed that the indications for operative intervention included the following: gapping at the zone of injury (86.9%); high functional demands of the patient (86.7%); symptomatic displaced bony avulsions (74.7%); and proximal free tendon injuries with functional compromise refractory to non-operative treatment (71.4%). Panel members agreed that surgical intervention had the capacity to restore anatomy and function, while reducing the risk of injury recurrence (86.7%). The consensus group did not support the use of corticosteroids or endoscopic surgery without further evidence.

These guidelines will help to further standardise the treatment of hamstring injuries and facilitate decision-making in the surgical treatment of these injuries.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_4 | Pages 28 - 28
1 Apr 2022
Scrimshire A Booth A Fairhurst C Coleman E Malviya A Kotze A Laverty A Davis G Tadd W Torgerson D McDaid C Reed M
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This trial aims to assess the effectiveness of quality improvement collaboratives as a technique to introduce large-scale change and improve outcomes for patients undergoing primary elective total hip or total knee arthroplasty.

41 NHS Trusts that did not have; a preoperative anaemia screening and optimisation pathways, or a methicillin sensitive Staphylococcus Aureus (MSSA) decolonisation pathway, in place were randomised to one of two parallel collaboratives in a two arm, cluster randomised controlled trial. Each collaborative focussed on implementing one of these two preoperative pathways. Collaboratives took place from May 2018 to November 2019. 27 Trusts completed the trial. Outcome data were collected for procedures between November 2018 and November 2019.

Co-primary outcomes were perioperative blood transfusion (within 7 days of surgery) and deep surgical site infections (SSI) caused by MSSA (within 90 days) for the anaemia and MSSA arms respectively. Secondary outcomes include deep and superficial SSIs (any organism), length of stay, critical care admissions, and readmissions. Process measures include the proportion of patients receiving each preoperative initiative.

19,254 procedures from 27 Trusts are included. Process measures show both preoperative pathways were implemented to a high degree (75.3% compliance in MSSA arm; 61.2% anaemia arm), indicating that QICs can facilitate change in the NHS. However, there were no improvements in blood transfusions (2.9% v 2.3% adjusted-OR 1.20, 95% CI 0.52–2.75, p=0.67), MSSA deep SSIs (0.13% v 0.14% adjusted-OR 1.01, 95%CI 0.42–2.46, p=0.98), or any secondary outcome.

Whilst no significant improvement in patient outcomes were seen, this trial shows quality improvement collaboratives can successfully support the implementation of new preoperative pathways in planned surgery in the NHS.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_4 | Pages 30 - 30
1 Apr 2022
Allport J Choudhury R Bruce-Wootton P Reed M Tate D Malviya A
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Periprosthetic joint infection (PJI) causes significant morbidity. Methicillin sensitive Staphylococcus Aureus (MSSA) is the most frequent organism, and the majority are endogenous. Nasal MSSA colonisation is a proven risk factor for S. aureus infection. Decolonisation reduces PJIs but there is a paucity of evidence comparing treatments. Aims; compare 3 nasal decolonisation treatments at (1) achieving MSSA decolonisation, (2) preventing PJI.

Our hospital trust introduced MSSA screening and decolonisation prior to hip and knee arthroplasty in 2010. Data was prospectively collected since 2013, including all MSSA carriers, decolonisation treatment received, MSSA status at time of surgery and all PJIs. Prior to 2017 MSSA carriers received nasal mupirocin or neomycin, from August 2017 until August 2019 nasal octenidine was used.

During the study period 15,958 primary hip and knee replacements were performed. 3,200 (20.1%) were MSSA positive at preoperative screening and received decolonisation treatment, 698 mupirocin, 1,210 neomycin and 1,221 octenidine. Mupirocin (89.1%) and neomycin (90.9%) were more effective at decolonisation than octenidine (50.0%, P<0.0001). There was no difference in S. aureus PJI rates (P=0.452). Of those negative at original screening 9.1% were positive on the day of surgery (1,164/12,758).

MSSA decolonisation is an effective method to decrease PJI rates but there is little research into the best treatment. Both mupirocin and neomycin are more effective than octenidine at achieving MSSA decolonisation. There was poor correlation between the MSSA status after treatment and PJI rates. There is debate if treatment should be targeted by screening or if all patients she be treated without screening. Global decolonisation without screening is supported by the 26.7% of carriers that were negative at original screening in our study.

Further research is needed comparing decolonisation treatments to reduce PJI rates and avoid the risk of drug resistance.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_4 | Pages 31 - 31
1 Apr 2022
Langton D Bhalekar R Joyce T Shyam N Nargol M Pabbruwe M Su E Nargol A
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Cobalt chrome alloy is commonly used in joint replacement surgery. However, it is recognised that some patients develop lymphocyte mediated delayed type hypersensitivity (DTH) responses to this material, which may result in extensive bone and soft tissue destruction.

Phase 1. United Kingdom: From an existing database, we identified extreme phenotype patient groups following metal on metal (MoM) hip resurfacing or THR: ALVAL with low wearing prostheses; ALVAL with high wear; no ALVAL with high wear; and asymptomatic patients with implants in situ for longer than ten years. Class I and II HLA genotype frequency distributions were compared between these patients’ groups, and in silico peptide binding studies were carried out using validated methodology.

Phase 2. United Kingdom: We expanded the study to include more patients, including those with intermediary phenotypes to test whether an algorithm could be developed incorporating “risk genotypes”, patient age, sex and metal exposure. This model was trained in phase 3.

Phase 3. United Kingdom, Australia, United States. Patients from other centres were invited to give DNA samples. The data set was split in two. 70% was used to develop machine learning models to predict failure secondary to DTH. The predictions were tested using the remaining blinded 30% of data, using time-dependent AUROCs, and integrated calibration index performance statistics.

A total of 606 DNA samples, from 397 males and 209 female patients, were typed. This included 176 from patients with failed prostheses, and 430 from asymptomatic patients at a mean of >10 years follow up. C-index and ROC(t) scores suggested a high degree of discrimination, whilst the IBS indicated good calibration and further backed up the indication of high discriminatory ability. At ten years, the weighted mean survival probability error was < 4%.

At present, there are no tests in widespread clinical use which use a patient's genetic profile to guide implant selection or inform post-operative management. The algorithm described herein may address this issue and we suggest that the application may not be restricted to the field of MoM hip arthroplasty.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_4 | Pages 32 - 32
1 Apr 2022
Fawi H Maughan H Fecht D Sterrantino A Lamagni T Wloch C de Preux L Norrish A Khanduja V
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Emerging evidence from different countries around the world is increasingly associating hip and knee replacements performed during the summer months with an increased risk of surgical site infection (SSI). We aimed to synthesise evidence on this phenomenon globally.

A systematic review was performed according to PRISMA guidelines using Medline, PubMed, and EMBASE from inception until August 2021 for relevant original articles without language restrictions. Meta-analysis was performed using random effects models to estimate and compare the pooled odds ratio (OR) and the confidence interval (CI) of operations undertaken during the summer season as defined by study authors.

Five studies from Canada, Japan, Pakistan, and the USA (n= 2) met the inclusion criteria. Data involving 1,589,207 primary hip and knee replacements, were included in the meta-analysis. There were 5985 superficial SSIs, out of total 420121 operations during the summer season, equating to a risk of 1.4%. During the other 3 seasons, there were 15364 Superficial SSIs out of 1169086 total operations, a risk of 1.3%.

The pooled OR highlighted increased odds of developing superficial SSI for patients who underwent joint replacements during the summer months (OR 1.29, 95% confidence interval 1.05 – 1.60, P < 0.0001); with evidence of significant heterogeneity.

Our preliminary meta-analysis suggests a 29% increased chance of having an SSI if the joint replacement was performed in the summer months. A high degree of heterogeneity was evident which warrants further exploration. Given the concerning consequences of developing wound infections after joint replacements, these findings may have important implications for informing individual patient-surgeon preoperative consent, surgical planning, and guiding future research.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_4 | Pages 36 - 36
1 Apr 2022
Holleyman R Kumar KS Khanduja V Malviya A
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This study aims to describe the characteristics and outcomes of patients who reported their pre-operative quality of life (QoL) was ‘worse than death’ (‘WTD’) prior to hip arthroscopy (HA) or peri-acetabular osteotomy (PAO).

Adult patients who underwent HA or PAO between 1st January 2012 and 31st October 2020 were extracted from the UK Non-Arthroplasty Hip Registry. International Hip Outcome Tool 12 (iHOT-12) and EuroQol-5 Dimensions (EQ-5D) index questionnaires were collected pre-operatively and at 6 and 12 months. WTD was defined as an EQ-5D score of less than zero. Chi-squared and t-tests were used to compare categorical and continuous variables respectively.

8493 procedures (6355 HA, 746 PAO) were identified in whom 7101 (84%) returned pre-operative EQ-5D questionnaires. 283 HA and 52 PAOs declared their pre-operative QoL to be ‘WTD’. Compared to those patients with pre-operative QoL ‘better than death’ (n=6072, control group) (EQ-5D ≥ zero) patients reporting ‘WTD’ function prior to HA were more likely to be female (66% vs 59%, p = 0.013), of higher body mass index (mean 27.6 kg/m2 (SD 5.9) vs 25.7 kg/m2 (4.5), p < 0.0001) however there were no statistically significant differences in mean age (36.8 vs 36.4 years), femoroacetabular impingement pattern, or femoral or acetabular cartilage lesion severity. There were no significant demographic differences for PAO.

For HA, iHOT-12 scores in WTD patients were significantly poorer pre- [10.8 (95% CI 9.6 to 12.0) vs 33.3 (32.8 to 33.8)] and 12 months post-operatively [34.9 (29.0 to 40.8) vs 59.3 (58.2 to 60.4)] compared to controls. Whilst the majority of patients saw improvement in their scores (p <0.0001), a significantly smaller proportion achieved the minimum clinically important difference for iHOT-12 by 12 months. (51% in the WTD group vs 65% in the control group). Similar trends were observed for PAO.

Patients with WTD quality of life may benefit less from hip preservation surgery and should be counselled accordingly regarding expectations. Although the scores improve, only 51% achieve scores beyond MCID.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_4 | Pages 9 - 9
1 Apr 2022
Williams S Pryce G Board T Isaac G Williams S
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The 10 year survivorship of THR is generally over 95%. However, the incidence of revision is usually higher in year one. The most common reason being dislocation which at least in part is driven by inadequate range of motion (ROM) leading to impingement, subluxation and ultimately dislocation which is more frequently posterior. ROM is affected by patient activity, bone and component geometry, and component placement. To reduce the incidence of dislocation, supported by registry data, there has been an increase in the use of so-called ‘lipped’ liners. Whilst this increases joint stability, the theoretical ROM is reduced. The aim of this study was to investigate the effect of lip placement on impingement.

A rigid body geometric model was incorporated into a CT scan hemi-pelvis and femur, with a clinically available THR virtually implanted. Kinematic activity data associated with dislocation was applied, comprising of five posterior and two anterior dislocation risk activities, resulting from anterior and posterior impingement respectively. Cup inclination and anteversion was varied (30°-70°, 0°-50° respectively) to simulate extremes of clinical outcomes. The apex position of a ‘lipped’ liner was rotated from the superior position, anteriorly and posteriorly in steps of 45°. Incidence and location of implant and bone impingement was recorded in 5346 cases generated.

A liner with the lip placed superior increased the occurrence of implant-implant impingement compared with a neutral liner. Rotation of the lip from superior reduced this incidence. This effect was more marked with posterior rotation which after 90° reduced anterior impingement to levels similar to a neutral liner. Complete inversion of the lipped liner reduced impingement, but this and anterior rotation both negate its function – additional stability.

This study comprises one bone geometry and component design and one set of activity profiles. Nevertheless, it indicates that appropriate lip placement can minimise the likelihood of impingement for a range of daily activities whilst still providing additional joint stability.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_4 | Pages 10 - 10
1 Apr 2022
Fontalis A Hansjee S Vanhegan I Ahmad SA Ogilvie A Giebaly D Kayani B Haddad FS
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Cementless stem designs in total hip arthroplasty differ in relation to geometry and area of fixation. We utilised radiostereometric analysis (RSA) to evaluate the 2-year migration of a novel, short, proximally coated femoral stem.

30 participants undergoing primary total hip replacement for any cause (rheumatoid or inflammatory arthritis, osteoarthritis) were prospectively recruited in this study. Osteoporotic patients and cases of suspected infection were excluded. All patients received a short blade stem, proximally coated with a reduced lateral shoulder and narrow triple taper geometry to minimise bone removal. RSA radiographs were performed post-operatively and at 6 weeks, 6 months, 1- and 2 years. The Harris Hip Score (HHS), Oxford Hip Score (OHS) and EQ-5D were collected at baseline and at 2 years post-operatively. The stability of implants and complications were captured during each follow-up visit.

A total of 14 female and 16 male patients were recruited with a mean age of 64.8 (range 47 to 75). At two years the mean subsidence of the stem was 0.34 mm (SD 0.62) and the total migration 0.74 mm (SD 0.60). The mean medial translation at two years was 0.059 (0.24) and the mean anterior translation 0.12 (0.59) respectively. Baseline PROM scores improved significantly at 2-years from pre-operatively (median and interquartile range): HHS from 33 (18.25) to 92 (19), EQ5D from 0.5 (0.35) to 0.94 (0.17), OHS from 21 (18.25) to 42 (4.25). P-value for all comparisons was <0.001. 2-year follow up data revealed no complications. There were no stem revisions in study participants and no heterotopic ossifications were identified on radiographs.

2-year migration results of a cementless, short blade, proximally coated tapered femoral stem using RSA, showed the stem exhibits a predictable migration pattern and achieves initial stability. This is highly likely to translate to mid and long-term stability, which needs to be corroborated by long-term outcome studies. Furthermore, participants demonstrated excellent clinical, patient reported and radiological outcomes after 2 years of follow up to support expansion in the use of this prosthesis.