Better early functional outcome after short stem total hip arthroplasty? A prospective blinded randomised controlled multicentre trial comparing the Collum Femoris Preserving stem with a Zweymuller straight cementless stem total hip replacement for the treatment of primary osteoarthritis of the hip

Short versus conventional straight stem in uncemented total hip arthroplasty: functional outcomes up to 5 years and survival up to 12 years: secondary results of a randomized controlled trial

BACKGROUND AND PURPOSE

To date, the mid- and long-term outcomes of the Collum Femoris Preserving (CFP) stem compared with conventional straight stems are unknown. We aimed to compare physical function at a 5-year follow-up and implant survival at an average of 10-year follow-up in an randomized controlled trial (RCT).

METHODS

This is a secondary report of a double-blinded RCT in 2 hospitals. Patients aged 18-70 years with hip osteoarthritis undergoing an uncemented primary THA were randomized to a CFP or a Zweymüller stem. Patient-reported outcomes, clinical tests, and radiographs were collected at baseline, 2, 3, 4, and 5 years postoperatively. Primary outcome was the Hip disability and Osteoarthritis Outcome Score (HOOS) function in activities of daily living (ADL) subscale. Secondary outcomes were other patient-reported outcomes, clinical tests, adverse events, and implant survival. Kaplan-Meier and competing risk survival analyses were performed with data from the Dutch Arthroplasty Registry.

RESULTS

We included 150 patients. Mean difference between groups on the HOOS ADL subscale at 5 years was -0.07 (95% confidence interval -5.1 to 4.9). Overall survival was 92% for the CFP and 96% for the Zweymüller stem. No significant difference was found.

CONCLUSION

No significant differences were found in physical function at 5-year and implant survival at 10-year follow-up between the CFP and Zweymüller stems. When taking cup revisions into account, the CFP group showed clinically inferior survival.

No difference in outcome or migration but greater loss of bone mineral density with the Collum Femoris Preserving stem compared with the Corail stem: a randomized controlled trial with five-year follow-up

AIMS

The aim of this study was to compare the mid-term patient-reported outcome, bone remodelling, and migration of a short stem (Collum Femoris Preserving; CFP) with a conventional uncemented stem (Corail).

METHODS

Of 81 patients who were initially enrolled, 71 were available at five years' follow-up. The outcomes at two years have previously been reported. The primary outcome measure was the clinical result assessed using the Oxford Hip Score (OHS). Secondary outcomes were the migration of the stem, measured using radiostereometric analysis (RSA), change of bone mineral density (BMD) around the stem, the development of radiolucent lines, and additional patient-reported outcome measures (PROMs).

RESULTS

There were no statistically significant differences between the groups regarding PROMs (median OHS (CFP 45 (interquartile range (IQR) 35 to 48); Corail 45 (IQR 40 to 48); p = 0.568). RSA showed stable stems in both groups, with little or no further subsidence between two and five years. Resorption of the femoral neck was evident in nine patients in the CFP group and in none of the 15 Corail stems with a collar that could be studied. Dual X-ray absorbiometry showed a significantly higher loss of BMD in the proximal Gruen zones in the CFP group (mean changes in BMD: Gruen zone 1, CFP -9.5 (95% confidence interval (CI) -14.8 to -4.2), Corail 1.0 (95% CI 3.4 to 5.4); Gruen zone 7, CFP -23.0 (95% CI -29.4 to -16.6), Corail -7.2 (95% CI -15.9 to 1.4). Two CFP stems were revised before two years' follow-up due to loosening, and one Corail stem was revised after two years due to chronic infection.

CONCLUSION

The CFP stem has a similar clinical outcome and subsidence pattern when compared with the Corail stem. More pronounced proximal stress-shielding was seen with the CFP stem, suggesting diaphyseal fixation, and questioning its femoral neck-sparing properties in the long term. Cite this article: Bone Joint J 2022;104-B(5):581-588.

The Implant Proteome—The Right Surgical Glue to Fix Titanium Implants In Situ

Titanium implants are frequently applied to the bone in orthopedic and trauma surgery. Although these biomaterials are characterized by excellent implant survivorship and clinical outcomes, there are almost no data available on the initial protein layer binding to the implant surface in situ. This study aims to investigate the composition of the initial protein layer on endoprosthetic surfaces as a key initiating step in osseointegration. In patients qualified for total hip arthroplasty, the implants are inserted into the femoral canal, fixed and subsequently explanted after 2 and 5 min. The proteins adsorbed to the surface (the implant proteome) are analyzed by liquid chromatography–tandem mass spectrometry (LC-MS/MS). A statistical analysis of the proteins’ alteration with longer incubation times reveals a slight change in their abundance according to the Vroman effect. The pathways involved in the extracellular matrix organization of bone, sterile inflammation and the beginning of an immunogenic response governed by neutrophils are significantly enriched based on the analysis of the implant proteome. Those are generally not changed with longer incubation times. In summary, proteins relevant for osseointegration are already adsorbed within 2 min in situ. A deeper understanding of the in situ protein–implant interactions in patients may contribute to optimizing implant surfaces in orthopedic and trauma surgery.

Short-term clinical and radiological results of two different design metaphyseal fitting femoral stems in total hip arthroplasty: a prospective, randomized trial

Background

There is great design variability on short femoral stems available on the market. This study aims to evaluate the short-term clinical and radiological results of two different design short femoral stems, both classified as shortened tapered stems.

Methods

From March 2016 to March 2018, a prospective, randomized, parallel-group design study was conducted to compare functional and radiological outcomes of 45 patients underwent THA using the Tri-Lock Bone Preservation Stem and 45 patients underwent THA with the Minima S stem at a minimum 2 years of follow-up. Patients were assessed clinically and radiographically prior to surgery as well as at 3, 6, 12, and 24 months postoperatively. Primary outcomes were the change in health-related quality of life assessed with Western Ontario and McMaster Universities Osteoarthritis Index and 36-Item Short Form Health Survey and also the incidence of all hip-related complications. Secondary aims included hip function evaluated with the Harris hip score, rates of patient satisfaction, and the outcomes of a detailed radiological analysis.

Results

There were no significant differences between the 2 study groups in terms of patient-reported outcomes measurements, satisfaction scores, and complication rates at any of the measurement times. In both groups, stable fixation and radiographic osseointegration were achieved. However, analysis of the calcar region showed that 57.8% and 28.9% of patients had grade 1 or 2 stress shielding, in Tri-Lock and Minima S implantation group, respectively (p=0.015). Regarding coronal alignment, stems were placed in slight varus, valgus, and neutral position in 51.1%, 13.3%, and 35.6% of patients, respectively, in Tri-Lock BPS group. The Minima S stem was implanted at slight varus and valgus in 60% and 40% of patients, respectively, and neither stem in the exact neutral position.

Conclusions

Both different design short femoral stems demonstrated excellent clinical performance at short-term follow up. Nevertheless, concerns were raised regarding the incidence of stress shielding phenomenon and mild discrepancies in coronal stem alignment during implantation. The clinical impact of these observations should be further evaluated through larger cohorts and longer follow-up.

Trial registration

ISRCTN registry, ISRCTN10096716. Registered on May 8, 2018—Retrospectively registered

A comparison of short-stem prostheses and conventional stem prostheses in primary total hip arthroplasty: a systematic review and meta-analysis of randomized controlled trials

Background

In total hip arthroplasty (THA), short-stem prostheses (SS) were designed to achieve better preservation of proximal femoral bone stock and stability than conventional stem prostheses (CS), however these effects are controversial. We aimed perform a systematic review and meta-analysis to evaluate the effectiveness of SS and CS in primary THA.

Methods

Relevant randomized controlled trials (RCTs) involving the comparison of SS and CS in primary THA were screened using the electronic databases PubMed, Embase and Web of Science. Data were analyzed with the RevMan 5.3 software program and evaluated with mean difference (MD), risk ratio (RR) and 95% confidence intervals (CIs) by random or fixed-effect models.

Results

Sixteen RCTs involving 1,233 patients (1,486 hips) were included. Compared with CS, the incidence of thigh pain was significantly reduced with Proxima SS (RR 0.13, 95% CI, 0.03–0.51; P=0.004). Bone mineral density (BMD) with femoral neck-preserved SS [SS (I)] showed less decrease in Gruen zone 1 (MD 14.60, 95% CI, 10.67–18.54; P<0.00001) and Gruen zone 7 (MD 9.72, 95% CI, 5.21–14.23; P<0.0001) than CS. However, the changes of BMD were not significantly different between the SS without femoral neck preservation group [SS (II)] and the CS group. In addition, no significant differences were found in the revision rate, Harris Hip Score (HHS), or maximum total point motion (MTPM) between the SS and CS groups.

Conclusions

The results of this study showed that compared with CS, Proxima SS decreased the incidence of thigh pain and that SS (I) provided better proximal bone remodeling than CS. But the revision rates, HHS, and MTPM between SS and CS were similar. However, the findings of this meta-analysis require further verification in high-quality RCTs.

A comparison of patient-reported outcome measures (PROMs) between short and conventional stem hip replacements: a systematic review and meta-analysis

INTRODUCTION

Short stem hip replacements may allow preservation of proximal bone stock and minimise soft tissue disruption, easing future revision surgery. However patient satisfaction with these implants must be determined before widespread use. We aimed to compare patient reported outcome measures (PROMs) between short and conventional stem hip replacements.

METHODS

A systematic review was conducted according to PRISMA guidelines for studies comparing short and conventional stem hip replacements with validated PROMs. Meta-analyses were performed for studies reporting Harris Hip and WOMAC scores. Study bias was assessed with the Cochrane Risk of Bias tool and Newcastle-Ottawa Scale.

RESULTS

24 studies, incorporating 2593 total hip replacements were included for qualitative analysis. 17 studies were included in the meta-analyses. Of the 7 excluded, 1 study reported the Japanese Orthopaedic Association score and 2 others reported the Oxford Hip score. All three showed no difference between the stems. A meta-analysis of 17 studies reporting Harris hip scores showed no statistically significant difference between short and conventional stems (standard mean difference (SMD) -0.06, 95% CI -0.20-0.07, p = 0.35). 6 studies reported WOMAC scores with higher scores indicating worse outcome. No difference was seen between the two groups (SMD 0.21, 95%CI, -0.01-0.42, p = 0.06). 4 studies reported higher WOMAC scores as better. Once again, a meta-analysis showed no statistically significant difference between the stems (SMD 0.28, 95% CI -0.07-0.63, p = 0.12).

CONCLUSIONS

Our systematic review showed no difference in PROMs between short and conventional stem total hip replacements. This is in keeping with previous evidence but is a more comprehensive analysis. Short stems may have an important role in younger individuals as they allow preservation of proximal femoral bone, minimal access surgery and are amenable to abnormal anatomy. The current literature is hindered by non-uniform methodologies and outcome assessments across studies. Further, standardised, high quality evidence is required before widespread changes in practice.

Surgeon-stratified cohort analysis of 1976 cementless Zweymüller total hip arthroplasties from a single hospital with 23,255 component years of follow-up

INTRODUCTION

The third-generation Zweymüller hip endoprosthesis has been used for decades with excellent results in arthroplasty registries, but surgeon-stratified reports on this implant are still scarce. The aim of the presented single-hospital cohort analysis of the third-generation Endoplus-Zweymüller primary total hip arthroplasty was to determine implant survival rates until the first revision/removal at 10/15/20/25 years after implantation and to find out whether implant survival depended on the operating surgeon, patient's age and gender, operated side (right/left), season of the year and the set of implanted components (SL-PLUS femur, BICON-PLUS acetabulum or both components).

MATERIALS AND METHODS

The retrospective observational cohort study included 1976 consecutive patients with primary BICON/SL-PLUS Zweymüller hip endoprosthesis implanted at the same operating theater block of the University Medical Centre Ljubljana, Department of Orthopaedic Surgery (Ljubljana, Slovenia) between January 1, 1993 and May 1, 2014. Survival analyses were performed with the Kaplan-Meier method and the Cox regression analysis after minimum 5 and maximum 26 years of follow-up.

RESULTS

At 10/15/20/25 years after implantation, the cumulative proportion of revision-free surviving Zweymüller total hip endoprostheses was 92/90/85/81% and the cumulative proportion with unremoved immobile components was 93/91/87/84%, respectively. After adjustment for age, gender and operated side, less experienced surgeons (odds ratios 2.34-5.00), season of the year at primary implantation (spring vs. winter odds ratio 1.74) and the use of BICON-PLUS acetabulum with femoral stem from another manufacturer (odds ratio 2.23) were significant risk factors of worse implant survival.

CONCLUSIONS

The study presents the largest published third-generation Zweymüller BICON/SL-PLUS total hip arthroplasty cohort from a single non-developmental hospital with 23,255 component years of observation. Study findings indicate the impact of environmental factors at primary implantation and variability between different surgeons on the long-term implant survival.

Fixation of the short global tissue-sparing hip stem

AIMS

Short, bone-conserving femoral components are increasingly used in total hip arthroplasty (THA). They are expected to allow tissue-conserving implantation and to render future revision surgery more straightforward but the long-term data on such components is limited. One such component is the global tissue-sparing (GTS) stem. Following the model for stepwise introduction of new orthopaedic implants, we evaluated early implant fixation and clinical outcome of this novel short-stem THA and compared it to that of a component with established good long-term clinical outcome.

METHODS

In total, 50 consecutive patients ≤ 70 years old with end-stage symptomatic osteo-arthritis were randomized to receive THA with the GTS stem or the conventional Taperloc stem using the anterior supine intermuscular approach by two experienced hip surgeons in two hospitals in the Netherlands. Primary outcome was implant migration. Patients were followed using routine clinical examination, patient reported outcome using Harris Hip Score (HHS), Hip Disability And Osteoarthritis Outcome Score (HOOS), EuroQol five-dimension questionnaire (EQ5D), and Roentgen Stereophotogrammetric Analysis (RSA) at three, six, 12, and 24 months. This study evaluated the two-year follow-up results.

RESULTS

In addition to the initial migration pattern of distal migration (subsidence, Y-translation) and retroversion (Y-rotation) also exhibited by the Taperloc stem, the GTS stem showed an initial migration pattern of varization (X-translation combined with Z-rotation) and posterior translation (Z-translation). However, all components stabilized aside from one Taperloc stem which became loose secondary to malposition and was later revised. Clinical outcomes and complications were not statistically significantly different with the numbers available.

CONCLUSION

A substantially different and more extensive initial migration pattern was seen for the GTS stem compared to the Taperloc stem. Although implant stabilization was achieved, excellent long-term survival similar to that of the Taperloc stem should not be inferred. Especially in the absence of clinically proven relevant improvement, widespread usage should be postponed until long-term safety has been established. Cite this article: Bone Joint J 2020;102-B(6):699-708.

Short stems for total hip replacement among middle-aged patients

INTRODUCTION

The purpose of the present study was to investigate the role of short stem implants for primary total hip arthroplasty in middle-aged patients. For this purpose, a meta-analysis of the current literature was conducted. The focus was on clinical outcomes,radiological parameters, and further complications of both components.

MATERIAL AND METHODS

The study was performed according to the PRISMA guidelines. All randomized and non-randomized clinical trials comparing short stem versus standard stem prostheses for THA were considered for inclusion. Only studies reporting data concerning uncemented stems for primary total hip arthroplasty were included. Only studies reporting data concerning patients with a mean age of 45 to 69 were included.

RESULTS

A total of 2197 procedures in 2116 patients were analysed. The mean follow-up was 30.2 months. The short stem group showed a statistically significant higher WOMAC score and a reduced total estimated blood loss compared with the standard stem group. The short stem group showed a reduced rate of femoral fractures, dislocations, and revision, but without statistical significance.

CONCLUSIONS

According to the main findings of this meta-analysis and current evidence, we encourage the use of the uncemented short stems during primary total hip arthroplasty in middle-aged patients.

Sleep improvement after hip arthroplasty: a study on short-stem prosthesis

PURPOSE

The purpose of this study was to evaluate sleep disturbance prospectively before and after short-stem hip arthroplasty.

METHODS

A prospective study on 25 patients undergoing a primary unilateral total short-stem hip replacement was conducted. Patients were observed for six months. To evaluate the sleep quality and daytime sleepiness, the Pittsburgh Sleep Quality Index and Epworth Sleepiness Scale were used. To assess the general physical health status, we used the Short Form 36 Health Survey (SF-36). Pain was recorded on a visual analog scale.

RESULTS

The physical health status of the patients improved significantly (p < 0.05) during the six month follow-up period in seven out of nine categories. During the first post-operative week, the sleep quality stayed on an equal level to the pre-operative state, following a steady improvement over the next months (6 months p = 0.00). The daytime sleepiness showed a significant improvement during all the follow-ups (6 months p = 0.00). Pain decreased significantly from baseline to six months post-operatively (p = 0.00). There was no correlation between pain and sleep quality or pain and daytime sleepiness.

CONCLUSION

According to our results, patients undergoing short-stem total hip arthroplasty can expect a 50% improvement of sleep quality and physical function six months after surgery.

Increased Persistent Mid-Thigh Pain After Short-Stem Compared With Wedge-Shaped Straight-Stem Uncemented Total Hip Arthroplasty at Medium-Term Follow-Up: A Randomized Double-Blinded Cross-Sectional Study

BACKGROUND

Femoral prosthesis design may impact the frequency of mid-thigh pain. We compared current, incidental, and persistent mid-thigh pain between the short-stem, Collum Femoris femur prosthesis, and the wedge shaped straight-stem, Zweymüller femur prosthesis and studied the associations between demographics, radiographic measurements, and mid-thigh pain.

METHODS

We contacted patients from a randomized controlled trial who underwent uncemented total hip arthroplasty (THA) for hip osteoarthritis at a mean follow-up of 44 months (range 24-64 months). Patients were specifically assessed for current (during assessment), incidental (any time postoperatively for >1 week) mid-thigh pain, and persistent (any time postoperatively for >2 years) mid-thigh pain. Furthermore, we used regression analysis to study associations between demographics, radiographic measurements, and mid-thigh pain.

RESULTS

One hundred forty of 150 patients (93%) responded to our assessment. Mean age at the time of operation was 62 years (±7.0). Current mid-thigh pain occurred in 16 patients (23%) in the Collum Femoris Preserving (CFP) group compared with 10 patients (14%) in the Zweymüller group (P = .192). Incidental mid-thigh pain occurred in 24 patients (34%) in the CFP group compared with 15 patients (21%) in the Zweymüller group (P = .090). Persistent mid-thigh pain was found in 13 patients (19%) in the CFP group compared with five patients (7%) in the Zweymüller group (P = .043). Varus malalignment (odds ratio 1.819 [95% confidence interval 1.034-3.200]) and leg lengthening (odds ratio 1.107 per cm lengthening [95% confidence interval 1.026-1.195]) showed significant associations with mid-thigh pain.

CONCLUSIONS

We found more persistent mid-thigh pain after short-stem uncemented THA compared to wedge-shaped straight-stem uncemented THA during medium-term follow-up. Varus malalignment and leg lengthening were associated with mid-thigh pain.

Intrasurgical Protein Layer on Titanium Arthroplasty Explants: From the Big Twelve to the Implant Proteome

PURPOSE

Aseptic loosening in total joint replacement due to insufficient osteointegration is an unsolved problem in orthopaedics. The purpose of the study is to obtain a picture of the initial protein adsorption layer on femoral endoprosthetic surfaces as the key to the initiation of osseointegration.

EXPERIMENTAL DESIGN

The paper describes the first study of femoral stem explants from patients for proteome analysis of the primary protein layer. After 2 min in situ, the stems are explanted and frozen in liquid nitrogen. Proteins are eluted under reducing conditions and analyzed by LC-MS/MS.

RESULTS

After exclusion of proteins identified by a single peptide, the implant proteome is found to consist of 2802 unique proteins. Of these, 77% are of intracellular origin, 9% are derived from the plasma proteome, 8% from the bone proteome, and four proteins with highest specificity score could be assigned to the bone marrow proteome (transcriptome). The most abundant protein in the adsorbed total protein layer is hemoglobin (8-11%) followed by serum albumin (3.6-6%).

CONCLUSIONS

A detailed knowledge of the initial protein film deposited onto the implants, as demonstrated here for the first time, may help to understand and predict the response of the osseous microenvironment to implant surfaces.

Characteristics Associated With Physical Function Trajectories in Older Adults With Cancer During Chemotherapy

CONTEXT

Studies on physical function trajectories in older adults during chemotherapy remain limited.

OBJECTIVES

The objective of this study was to determine demographic, clinical, and symptom characteristics associated with initial levels as well as trajectories of physical function over two cycles of chemotherapy in adults aged ≥65 years with breast, gastrointestinal, gynecological, or lung cancer.

METHODS

Older adults with cancer (n = 363) who had received chemotherapy within the preceding four weeks were assessed six times over two cycles of chemotherapy using the Short Form-12 Physical Component Summary (PCS) score. Hierarchical linear modeling was used to evaluate for interindividual variability in initial levels and trajectories of PCS scores.

RESULTS

Mean age was 71.4 years (SD 5.5). Mean PCS score at enrollment was 40.5 (SD .45). On average, PCS scores decreased slightly (i.e., 0.21 points) at each subsequent assessment. Lower PCS scores at enrollment were associated with older age, greater comorbidity, being unemployed, lack of regular exercise, higher morning fatigue, lower evening energy, occurrence of pain, lower trait anxiety, and lower attentional function. Only higher morning fatigue and lower enrollment PCS scores were associated with decrements in physical function over time.

CONCLUSION

While several symptoms were associated with decrements in PCS scores at enrollment in older adults with cancer receiving chemotherapy, morning fatigue was the only symptom associated with decreases in physical function over time. Regular assessments of symptoms and implementation of evidence-based interventions should be considered to maintain physical function in older adults during chemotherapy.

Can Arthroplasty Stem INfluence Outcome? (CASINO): a randomized controlled equivalence trial of 125 mm versus 150 mm Exeter V40 stems in total hip arthroplasty

Background

The use of shorter length femoral stems during total hip arthroplasty has been suggested to accommodate wider patient femoral geometry and offer maximal bone preservation. However, cemented short-stem designs may increase the risk of varus stem malalignment and influence patient outcomes.

Methods/Design

CASINO is a multi-centre randomised equivalence trial that will recruit 220 patients undergoing total hip arthroplasty for osteoarthritis at two NHS hospitals in Scotland. Patients will be aged 45–80, undergoing unilateral primary hip arthroplasty, with no plan for contralateral procedure within the study timeframe, and able to comply with the protocol. Participants will be randomised to receive either a short (125 mm) or a standard (150 mm) Exeter V40 stem. The Contemporary acetabular component will be used in all cases. All implants will be cemented.

Patient pain, function and satisfaction will be assessed using change from baseline measurement in Oxford Hip Score, Forgotten Joint Score, EQ-5D, pain numerical rating scores, and patient satisfaction questionnaire at baseline and at 1 and 2 years following surgery. Radiographic assessment will evaluate stem position and will be appraised by independent reviewers. Patients will be blind to implant allocation.

Discussion

Stem length may be associated with outcome; however, we can find no randomised trial in which researchers investigated the effect of stem length on patient outcome following cemented total hip arthroplasty. The aim of this trial is to determine if the use of short cemented stems offers equivalent patient outcomes to those achieved following surgery with standard length stems.

Trial registration

International Standard Randomised Controlled Trial Number, ISRCTN13154542, Registered on 30 June 2017.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2621-8) contains supplementary material, which is available to authorized users.