Greater trochanteric pain after total hip arthroplasty: the incidence, clinical outcome and associated factors

Impact of the hip-spine relationship and patient-perceived leg length discrepancy after total hip arthroplasty: A retrospective study

PURPOSE

Patient-perceived leg length discrepancy (PLLD) is one of the major postoperative complications of total hip arthroplasty (THA). This study aimed to identify factors that cause PLLD following THA.

MATERIALS AND METHODS

This retrospective study included a series of consecutive patients who underwent unilateral THA between 2015 and 2020. Ninety-five patients who underwent unilateral THA with postoperative radiographic leg length discrepancy (RLLD) ≤1 cm were classified into two groups according to the direction of preoperative pelvic obliquity (PO). Standing radiographs of the hip joint and whole spine were obtained before and one year after THA. The clinical outcomes and the presence or absence of PLLD was confirmed one year after THA.

RESULTS

Sixty-nine patients were classified as having type 1 PO (rising toward the unaffected side) and 26 were classified as having type 2 PO (rising toward the affected side). Eight patients with type 1 PO and seven with type 2 PO had PLLD postoperatively. In the type 1 group, patients with PLLD had larger preoperative and postoperative PO values and larger preoperative and postoperative RLLD than those without PLLD (p = 0.01, p < 0.001, p = 0.01, and p = 0.007, respectively). In the type 2 group, patients with PLLD had larger preoperative RLLD, larger amount of leg correction, and a larger preoperative L1-L5 angle than those without PLLD (p = 0.03, p = 0.03, and p = 0.03, respectively). In type 1, postoperative PO was significantly associated with postoperative PLLD (p = 0.005), but spinal alignment was not an indicator of postoperative PLLD. The area under the curve (AUC) for postoperative PO was 0.883 (good accuracy) with a cut-off value was 1.90° CONCLUSION: Rigidity of the lumbar spine might lead to postoperative PO as a compensatory movement, resulting in PLLD after THA in type 1. Further research on the relationship between flexibility of the lumbar spine and PLLD is needed.

An Unconventional Solution for Persistent Lateral Hip Prosthetic Friction Syndrome (LHPFS) after Revision Total Hip Arthroplasty

We report on a 77-year-old male patient, who presented with excessive bone loss at the area of the greater trochanter after several hip revision surgeries resulting in a persistent friction syndrome caused directly by the rough surface and sharp edges of the prosthetic shoulder of a well-fixed Wagner-type revision stem. Surgery was performed by creating a cemented neotrochanter with an attached polyester patch around the proximal lateral shaft and performing a Z-plasty of the iliotibial tract. Twelve months postoperatively, the patient reported a reduction in subjective pain of 50% and improvement of the Harris Hip Score from 45 to 75 points. Without a definition in the current literature, the authors propose the term "lateral hip prosthetic friction syndrome" (LHPFS) to describe this medical condition.

Management of Greater Trochanteric Pain Syndrome After Total Hip Arthroplasty: Practice Patterns and Surgeon Attitudes

INTRODUCTION

Greater trochanteric pain syndrome (GTPS) or trochanteric bursitis is described as pain on the lateral side of the hip that does not involve the hip joint and can be elicited clinically by palpation over the greater trochanter. To date, there remains no consensus on clinical guidelines for either diagnosis or management of GTPS.

METHODS

To understand the practice patterns, beliefs, and attitudes relating to the management of GTPS after total hip arthroplasty, a survey was developed and completed by Canadian arthroplasty surgeons. The final survey consisted of 23 questions divided into three sections: 1) screening questions; 2) demographic information; and 3) practice patterns, attitudes, and beliefs.

RESULTS

Most surgeons use physical examination alone for diagnosis. A detailed analysis indicates that surgeons primarily treat GTPS with oral anti-inflammatories (57.1%), structured physiotherapy (52.4%), and steroid injections (45.2%). Management options are typically nonsurgical and comprise a combination of either unstructured or targeted physiotherapy, corticosteroid injections, or platelet-rich plasma.

DISCUSSION

There remains an absence of clinical consensus for the diagnosis and management of GTPS after total hip arthroplasty. Physical examination is most often relied on, regardless of the availability of imaging aids. While common treatments of GTPS were identified, up to one-third of patients fail initial therapy.

Optimising Soft-Tissue Balancing in Hip Hemiarthroplasty Surgery Using a Simple Planning Protocol

Introduction Intracapsular neck of the femur fractures are some of the most common fragility fractures with significant morbidity and mortality. Cemented hemiarthroplasty is the standard treatment in most cases. Restoring the horizontal offset and leg length is important to optimize the outcome of hip hemiarthroplasty. Preoperative templating based on a scaled radiograph is common prior to total hip arthroplasty surgery to achieve optimum offset and leg length. It is not routine to have scaled radiographs available prior to a hemiarthroplasty surgery. Our simple non-scaled radiograph templating protocol (NSRTP) was introduced to help establish the correct offset and leg length in the absence of scaled radiographs. Methods A retrospective, comparative, case-control study was carried out in an acute hospital setting. Scaled radiographs were not available for any patients in the study, as is usual for hemiarthroplasty patients in our hospital. One group had surgery without any templating. The other group had surgery using the NSRTP. The NSRTP determined optimal ipsilateral offset based on preoperative measurement of the contralateral hip offset and ipsilateral head diameter on unscaled radiographs together with intraoperative measurement of the diameter of the ipsilateral femoral head removed at surgery. To help achieve the correct length, the NSRTP also included assessment and restoration of the contralateral greater trochanter tip-to-head relationship. The neck cut was tailored to restore the correct relationship. Results Twenty-three patients underwent hemiarthroplasty surgery without any templating and 23 had surgery using the NSRTP. The implants used were C-STEM™ (DePuy Synthes, Raynham, Massachusetts, United States) and SPECTRON (Smith & Nephew plc, London, United Kingdom); stems were used together with monopolar heads. The stems were available in standard and high offset versions and with a variety of neck lengths, allowing the correct combination to be selected to restore offset. When the NSRTP was used, horizontal offset and leg length were restored to within 2 mm of the contralateral hip in 22 patients out of 23. There was a statistically significant improvement in restoration of offset and leg length when the NSRTP was used, compared to the control group. Conclusion Restoration of the offset and leg length is important to maximize the outcome of hip arthroplasty surgery. Preoperative templating is helpful to achieve offset and leg length in total hip replacement. In the absence of scaled radiographs, NSRTP enables restoration of offset and leg length to within 2 mm of normal in more than 96% of patients. This protocol requires knowledge of the offset of the hemiarthroplasty stems being used, which is easily available from the relevant manufacturer.

Psychometric Characteristics, Cross-Cultural Adaptation and Validation of the Slovenian Version of the Victorian Institute of Sports Assessments for Gluteal Tendinopathy Questionnaire (VISA-G)

Introduction

Greater trochanteric pain syndrome (GTPS) denotes several disorders around the lateral aspect of the hip. GTPS may develop in native hips as well as after total hip arthroplasty (THA). It is estimated that 5-12% of patients suffer from GTPS after primary THA. Despite the prevalence of GTPS, it is hard to diagnose and manage it properly. The VISA-G questionnaire was developed as a patient-reported outcome measurement tool for evaluation of GTPS. The aims of the present study were to evaluate the reliability of the VISA-G Slovenian and its construct and criterion validity.

Methods

After the finalization of the VISA-G Slovenian translation procedure, 59 patients with a painful trochanteric region planned for THA filled in the VISA-G Slovenian at the hospital on two occasions 5-7 days apart. On the first occasion, each patient also filled in the EQ-5D-5L questionnaire and the Harris Hip Score (HHS) was completed by the physiotherapist.

Results

The VISA-G Slovenian was found to have a test-retest reliability of ICC 0.977; 95% CI [0.96; 0.986]. Internal consistency was assessed with Cronbach's alpha 0.79. The statistically significant, but low, correlation between the HHS and VISA-G (r=0.48) was obtained. Concurrent validity of the VISA-G with the EQ-5D-5L showed moderate to strong correlations in Mobility, Self-Care, Usual Activities, Pain, EQ-5D-5L Index and EQ VAS, but low correlation in the Anxiety subscale. No floor and ceiling effect were obtained.

Conclusions

The VISA-G Slovenian has excellent psychometric properties needed to measure gluteal tendinopathy-related disability of patients in Slovenia. Thus, we recommend using the questionnaire for measuring trochanteric hip pain.

Femoral anteversion change is associated with ischiofemoral impingement after total hip arthroplasty: a retrospective CT evaluation

OBJECTIVES

We evaluated the relationship between femoral anteversion (FA), FA change, and ischiofemoral impingement (IFI) and the relationship between FA, femoral offset (FO), and greater trochanteric pain syndrome (GTPS) after total hip arthroplasty (THA).

MATERIALS AND METHODS

In this retrospective study, two readers assessed FA and FO on CT images of 197 patients following primary THA with an anterior surgical approach between 2014 and 2021. FA change was calculated relative to preoperative CT, while FO change was calculated relative to preoperative radiographs and classified as decreased (≥-5 mm), increased (≥ + 5 mm), or restored (± 5 mm). Clinical and imaging data were analyzed for IFI and GTPS after surgery. Group differences were evaluated using Student's t-test, chi-square analysis, and receiver operating characteristic (ROC) analysis.

RESULTS

The change in FA was 3.6 ± 3.3° to a postoperative FA of 22.5 ± 6.8°, while FO increased by 1.7 ± 3.5 mm to a postoperative FO of 42.9 ± 7.1 mm. FA and FA change were higher in patients with IFI (p ≤ 0.006), while no significant difference was observed for patients with and without GTPS (p ≥ 0.122). IFI was more common in females (p = 0.023). In the ROC analysis, an AUC of 0.859 was observed for FA change to predict IFI, whereas the AUC value was 0.726 for FA alone. No significant difference was found for FO change in patients with and without IFI or GTPS (p ≥ 0.187).

CONCLUSION

Postoperative FA, FA change, and female sex were associated with IFI after anterior-approached THA. The change in FA was a better predictor of IFI than absolute postoperative FA alone.

CLINICAL RELEVANCE STATEMENT

The findings of this study suggest that preservation of the preoperative femoral anteversion may reduce postoperative ischiofemoral impingement in patients undergoing total hip arthroplasty.

KEY POINTS

• Higher postoperative femoral anteversion and anteversion change were associated with ischiofemoral impingement. • Femoral anteversion change was a better predictor of impingement than absolute postoperative anteversion. • No significant association was found between femoral offset and postoperative hip pain.

The influence of anterior and posterior knot placement on hip function after total hip arthroplasty using a modified Dall's approach: a prospective non-randomised comparative study

BACKGROUND

The direct lateral modified Dall's approach for total hip arthroplasty (THA) provides an excellent vision of the hip joint by osteotomising the greater trochanter (GT). A robust method for the reattachment of osteotomised fragments is essential to prevent complications around the GT. Ultra-high molecular weight polyethylene cables are reported to be useful for reattachment; but the optimal suture method of these cables is unknown. The purpose of this study was to investigate the influence of the knot position on hip function after primary THA.

METHODS

In a prospective non-randomised study 216 primary THA were included, being scheduled for an operation with a modified Dall's approach. They were divided into 2 groups, anterior (A) and posterior (P) according to the knot position for the GT. Hip function was assessed using the Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ), pain visual analogue scale (VAS), satisfaction VAS and Merle d'Aubigne-Postel hip score at 3 and 6 months postoperatively. A logistic regression analysis was used to investigate factors influenced by the knot position.

RESULTS

Patient demographics were comparable between the 2 groups. Differences of the knot position did not affect the radiological failure rate of GT reattachment. Regression analysis showed a significantly positive impact on pain VAS and flexion range at 6 months postoperatively for posterior knot position.

CONCLUSIONS

For the reattachment of osteotomised fragments, the posterior knot may be superior to the anterior knot.

Incidence of and Risk Factors for Lateral Trochanteric Pain After Direct Anterior Approach Total Hip Arthroplasty

Lateral trochanteric pain (LTP) is a common complication after total hip arthroplasty (THA). The goals of this study were to report the incidence of LTP after direct anterior approach (DAA) THA, describe the treatment course and outcomes, and examine patient-specific and implant-related potential risk factors. A retrospective review identified patients who underwent primary DAA THA with at least 1-year follow-up. Postoperative functional outcome scores and LTP occurrence were recorded. Patient demographics, surgical indications, implant characteristics, medical comorbidities, and radiographic parameters were obtained. Logistic regression analysis was used to identify risk factors. A total of 610 THA procedures were performed for 563 patients (mean follow-up, 30.9±15.2 months). The overall incidence of LTP was 11.6%. All cases of LTP were successfully treated conservatively, although these patients, compared with patients who did not have postoperative LTP, experienced significantly lower functional outcome scores (Harris Hip Score, 96.6±4.7 [range, 55-100] vs 89.9±8.5 [range, 42-100], respectively; P<.001). Logistic regression analysis identified female sex (odds ratio, 2.30; 95% CI, 1.32-4.02), diabetes mellitus (odds ratio, 2.32; 95% CI, 1.11-4.88), hypertension (odds ratio, 1.94; 95% CI, 1.15-3.28), and the use of an offset acetabular liner (odds ratio, 2.50; 95% CI, 1.06-5.91) as independent risk factors for LTP. There was no correlation between LTP and radiographic parameters. The incidence of LTP after DAA THA is similar to reported rates for other THA surgical approaches. Female sex, medical comorbidities, and the use of offset acetabular liners are likely associated, and patients should be counseled appropriately. Postoperative LTP results in worse functional outcomes, although all cases can be treated conservatively. [Orthopedics. 2022;45(2):e79-e85.].

Greater trochanteric pain after primary total hip replacement, comparing the anterior and posterior approach: A secondary analysis of a randomized trial

BACKGROUND

Greater trochanteric pain (GTP) after total hip replacement is a common cause of residual lateral hip pain, regardless of the approach used. The goal of our study was to evaluate GTP after a direct anterior approach (DAA) compared to a posterior approach (PA) as well as the clinical outcomes of both approaches and answer the following: 1) What is the incidence of trochanteric pain after primary THA with two different surgical approaches? 2) What is the functional outcome of patients with GTP? 3) What proportion of patients with GTP resort to peritrochanteric injections?

HYPOTHESIS

Our hypothesis is that GTP is present with both approaches but satisfaction is lower with the PA.

PATIENTS AND METHODS

A secondary analysis of a previously published clinical trial with 55 total hip arthroplasty patients randomized in one of two surgical approaches: 27 patients underwent the anterior modified Hueter approach, while the other group of 28 patients were operated using the posterior approach. Study outcomes were Modified Harris Hip Score (MHHS), satisfaction score, pain when lying on the affected side, and requiring an injection. Hip offset, femur lateralization and leg lengthening were measured before and after surgery.

RESULTS

Forty-five patients were available for complete follow-up at a mean of 62 months (range: 48-74). The incidence of GTP was higher in the posterior approach [PA: 6/21 (29%) vs DAA 4/24 (17%)) (p=0.3). Patients operated through a PA experienced more pain [5/21 (24%) of patients; VAS=mean 5.3] when lying on their operated side, compared to DAA patients [2/24 (8%) of patients; VAS=mean 2) (p=0.2)]. However, MHHS, patient satisfaction with surgery, radiological assessment for hip offset, femur lateralization or leg lengthening, and injections required were similar for both approaches. Overall, satisfaction and functional outcome with surgery was significantly lower in GTP patients, regardless of the approach.

CONCLUSIONS

GTP impacts patient satisfaction and functional outcome in total hip arthroplasty patients. PA patients reported more trochanteric pain than DAA patients, which affected their clinical outcome.

LEVEL OF EVIDENCE

III.

Distal femoral cortical hypertrophy not associated with thigh pain using a short stem femoral implant

BACKGROUND

Thigh pain following a well-fixed total hip arthroplasty (THA) remains problematic and a source of patient dissatisfaction. The purpose of this study is to evaluate if the development of distal femoral cortical hypertrophy (DFCH) is associated with postoperative thigh pain after THA.

METHODS

All patients who underwent an uncomplicated primary THA via a direct anterior approach with the Taperloc Microplasty (Zimmer Biomet, Warsaw, IN, USA) implant between 2011 and 2015 were mailed a pain drawing questionnaire. Radiographs were reviewed at 1 year minimum to determine cortical thickness change from immediate post-op. Thigh pain was compared to DFCH. 293 patients were included in the study.

RESULTS

Mean follow-up was 3.2 years. A total of 218 hips (74%) had cortical hypertrophy in Gruen zone 3 and 165 hips (56%) had cortical hypertrophy in Gruen zone 5. 52 hips (18%) had ⩾25% cortical hypertrophy in zone 3 and 91 hips (31%) had ⩾25% cortical hypertrophy in zone 5. A total of 44 patients (15%) reported anterior thigh pain and 43 patients (15%) reported lateral thigh pain. Development of DFCH in either Gruen zone 3 or 5 was not associated with anterior or lateral thigh pain. Stem size was positively correlated with zone 3 hypertrophy and inversely related to zone 5 hypertrophy. Thigh pain was not associated with patient age, gender, activity level or stem size.

CONCLUSIONS

The development of distal femoral cortical hypertrophy after THA with a short stem implant was high, but not associated with patient-reported anterior or lateral thigh pain.

Lateral Trochanteric Pain Following Primary Total Hip Arthroplasty: Incidence and Success of Nonoperative Treatment

BACKGROUND

Our study aimed at quantifying the overall incidence of lateral trochanteric pain (LTP) following total hip arthroplasty (THA) and risk based on surgical approach. The success of conservative treatment and potential risk factors for failure of conservative treatment were evaluated.

METHODS

This is a retrospective review of patients who underwent primary THA between 2010 and 2019 and had a postoperative diagnosis of ipsilateral LTP. Chart review revealed patient demographics/comorbidities, preoperative diagnosis, surgical approach, femoral components, and nonoperative treatment modalities. Radiographic analysis was performed to measure leg length discrepancy, femoral offset, and femoral head lateralization.

RESULTS

The incidence of LTP following primary THA was 1.70% (573/33,761) with an average time to diagnosis of 27.3 months. The direct anterior approach demonstrated the highest risk and the direct lateral demonstrated the lowest risk for LTP (P < .001). Also, 82.4% (472/573) were diagnosed greater than 6 months postoperatively (P < .001). Of 573 patients, 95 (16.6%) were treated with physical therapy, home exercises, or oral medications with a success rate of 96.8% (92/95). Remaining 478 (83.4%) were treated with corticosteroid injection (CSI). And 89.5% (428/478) of the CSI cohort demonstrated clinical improvement with 3 or less CSIs. Risk factors for failure of conservative treatment were depression (P = .034), kidney disease (P = .040), and osteoporosis (P = .007).

CONCLUSION

Postoperative LTP after THA is rare with an incidence of 1.70%. The direct anterior approach presented higher risk of LTP. Non-CSI modalities and CSIs were both successful treatment options. In patients with depression, kidney disease, and osteoporosis, conservative treatment may be less efficacious.

A comparison of leg length discrepancy between direct anterior and anterolateral approaches in total hip arthroplasty

Background

Leg length discrepancy (LLD) after total hip arthroplasty (THA) is a known source of complications and a leading cause of litigation (J Bone Joint Surg Br 87:155–157, 2005). There are limited studies investigating surgical approach combined with the use of fluoroscopy intraoperatively and their potential effects on LLD after THA. The purpose of this study was to compare the direct anterior (DA) approach utilizing a fluoroscopic overlay technique and anterolateral (AL) approach and their potential effect on LLD.

Methods

We retrospectively reviewed 121 patients who had undergone primary THA from September 1, 2016 to November 1, 2018 by either DA or AL approach by two separate surgeons. Leg length discrepancies were measured on pre-operative post-anesthesia care unit (PACU) and on post-operative low anterior/posterior (AP) pelvis plain radiographs by two investigators blinded to each other’s measurements. To confirm inter-observer and intra-observer reliability between LLD measurements amongst investigators, a Pearson correlation test was performed. The primary outcome measurement was leg length discrepancy (LLD).

Results

We observed LLD > 1.0 cm and LLD > 1.5 cm in the DA and AL groups. The DA approach group showed a mean LLD of 4.5 mm against 7.76 mm in the AL group (p < 0.00001). There was a significantly higher rate of LLD in the AL group as compared to the DA group (LLD> 1 cm (28% vs. 8%, p = 0.0037) and LLD > 1.5 cm (7% vs. 0%, p = 0.0096). The LLD measurements showed strong correlation in terms of inter-observer (r = 0.95) and intra-observer reliability (r = 0.99) between the two investigators (p < 0.001).

Conclusion

In our patient cohort, the DA approach with fluoroscopic overlay technique had less LLD in comparison with the AL approach, suggesting that intraoperative fluoroscopic use does have an impact on LLD.

Restoration of leg length and offset correlates with trochanteric pain syndrome in total hip arthroplasty

Persistent pain around the greater trochanter is a common complication after total hip arthroplasty. Restoration of biomechanics such as leg length, femoral und acetabular offset is crucial in THA. The purpose of this study was to evaluate postoperative differences of these parameters after THA and to analyze their association to greater trochanteric pain syndrome. Furthermore, we aimed to evaluate the clinical relevance of trochanteric pain syndrome compared to patient reported outcome measures. 3D-CT scans of 90 patients were analyzed after minimalinvasive total hip arthroplasty and leg length, femoral and acetabular offset differences were measured. Clinical evaluation was performed three years after THA regarding the presence of trochanteric pain syndrome and using outcome measures. Furthermore, the patients' expectation were evaluated. Patients with trochanteric pain syndrome showed a higher absolute discrepancy of combined leg length, femoral and acetabular offset restoration compared to the non-operated contralateral side with 11.8 ± 6.0 mm than patients without symptoms in the trochanteric region with 7.8 ± 5.3 mm (p = 0.01). Patients with an absolute deviation of the combined parameters of more than 5 mm complained more frequently about trochanteric symptoms (29.2%, 19/65) than patients with a biomechanical restoration within 5 mm compared to the non-affected contralateral side (8.0%, 2/25, p = 0.03). Clinical outcome measured three years after THA was significantly lower in patients with trochanteric symptoms than without trochanteric pain (p < 0.03). Similarly, fulfillment of patient expectations as measured by THR-Survey was lower in the patients with trochanteric pain (p < 0.005). An exact combined restoration of leg length, acetabular and femoral offset reduces significantly postoperative trochanteric pain syndrome and improves the clinical outcome of the patients.

Influence of leg length inequalities on pelvis and spine in patients with total hip arthroplasty

Background

Leg length inequalities (LLIs) are a common finding in patients with a total hip arthroplasty (THA). Therefore, we compared the effects of simulated LLIs in patients with total hip arthroplasty (THA) with a matched control group.

Research question

Do LLIs lead to different effects on the musculoskeletal apparatus of patients with a THA then in a control group?

Methods

In 99 patients with a THA the effects of simulated LLIs were compared to a matched control group of 101 subjects without a hip arthroplasty. First, we compared methods for LLI quantification (tape measurements, pelvic x- ray and rasterstereography). Second, the effects of simulated LLIs on the spine and pelvis were evaluated in both groups using surface topography. LLIs of 5, 10, 15, 20 and 30 mm were simulated on both sides with a simulation platform. The changes of pelvic position (pelvic obliquity & pelvic torsion) and the effects on spinal posture (surface rotation & lateral deviation) were measured and analysed using a surface topography system.

Results

Mean LLI measured with a tape was 0.9 mm (SD +/- 14.8). Mean pelvic obliquity measured on x-rays was 1.2 mm (SD +/- 11.6) and with surface topography 0.9 mm (SD +/- 7.9). Simulated LLIs resulted in significant changes of pelvic position and spinal posture in the patient and control group. Interestingly, our study showed that simulated LLIs lead to greater changes in pelvic position (p<0.05) in patients with a THA.

Significance

This is the first study to demonstrate that LLIs might have a greater impact on the pelvic position of THA patients than in native hips, which could indicate that LLIs do need to be compensated differently in patients with THA than in patients without a THA.

Does the femoral offset affect replacements? The results from a National Joint Registry

BACKGROUND

Femoral component offset influences the torque forces exerted on a femoral stem and may therefore adversely affect femoral component survival. This study investigated the influence of femoral component offset on revision rates for primary total hip replacements (THR) registered on the New Zealand Joint Registry (NZJR).

METHODS

There were 106,139 primary THRs registered, resulting in 4960 revisions for any cause. There were 46,242 THRs performed using the five commonest femoral components listed on the NZJR. A total of 41,100 were done for primary osteoarthritis of which 40,548 had all the offset information available for analysis. We defined low offset as < 42 mm, standard as 42-48 mm and high offset as > 48 mm offset and examined revision rates according to the reasons for revision. We performed survival analyses for both cemented and uncemented femoral components grouped by the different offsets.

RESULTS

The all-cause revision rate was 0.54/100 component years (cys). Stems with < 42 mm offset had a revision rate of 0.58/100 cys (mean 0.58; 95% confidence interval (CI) 0.53-0.63), 42-48 mm offset 0.47 (95% CI 0.43-0.52) and > 48 mm offset 0.67 (95% CI 0.57-0.79). There was no significant difference in all-cause revision rates between varying stem offsets in uncemented stems adjusting for age and gender. In cemented stems both high and low offset stems were more likely to be revised. Uncemented stems of all offsets were more likely to undergo revision for femoral fracture.

CONCLUSIONS

Femoral component offset affects the overall all-cause revision rate of the most commonly used cemented stem, but not uncemented stem designs. In cemented stems offset influences the rate of revision for loosening and periprosthetic fractures.

Risk factors for conversion surgery to total hip arthroplasty of a hemiarthroplasty performed for a femoral neck fracture

INTRODUCTION

The purpose of this study was to determine risk factors for conversion to total hip arthroplasty (THA) in patients originally treated with hemiarthroplasty (HA) for displaced femoral neck fractures.

METHODS

In this case-controlled study, we identified 54 patients who were treated with HA for femoral neck fracture (FNF) who subsequently underwent conversion to THA at our institution between 2003 and 2013. We randomly selected 142 control patients who underwent HA for a displaced FNF without conversion surgery during the same time period. We compared demographic data, implant parameters, and radiographic data between the groups to identify risk factors for conversion surgery.

RESULTS

In the univariate analysis, younger age at index surgery (mean 75 vs. 80 years, p = 0.006), higher body mass index (26.1 vs. 23.7, p = 0.031), bipolar prosthesis (20% vs. 36%, p = 0.024), absence of dementia (6% vs. 23%, p = 0.01), increased leg length compared to contralateral limb (6.5 mm vs. 0.2 mm, p<0.001), and increased HA femoral head size compared to the contralateral femoral head (2.7 mm vs. 1.5 mm, p = 0.02) were associated with a significantly increased risk of conversion surgery. In the multivariate logistic regression, decreased age at index surgery, no dementia, use of a bipolar head, and increased leg length discrepancy (LLD) were associated with risk of conversion.

CONCLUSIONS

Patient characteristics, including younger age, increased BMI, and absence of dementia can lead to increased risk for conversion of HA to THA. Intraoperative considerations of head size and increase in ipsilateral LLD may increase the risk of conversion surgery. These factors should be considered by surgeons who employ HA for displaced FNFs.

Risk factors for conversion surgery to total hip arthroplasty of a hemiarthroplasty performed for a femoral neck fracture

INTRODUCTION

The purpose of this study was to determine risk factors for conversion to total hip arthroplasty (THA) in patients originally treated with hemiarthroplasty (HA) for displaced femoral neck fractures.

METHODS

In this case-controlled study, we identified 54 patients who were treated with HA for femoral neck fracture (FNF) who subsequently underwent conversion to THA at our institution between 2003 and 2013. We randomly selected 142 control patients who underwent HA for a displaced FNF without conversion surgery during the same time period. We compared demographic data, implant parameters, and radiographic data between the groups to identify risk factors for conversion surgery.

RESULTS

In the univariate analysis, younger age at index surgery (mean 75 vs. 80 years, p = 0.006), higher body mass index (26.1 vs. 23.7, p = 0.031), bipolar prosthesis (20% vs. 36%, p = 0.024), absence of dementia (6% vs. 23%, p = 0.01), increased leg length compared to contralateral limb (6.5 mm vs. 0.2 mm, p<0.001), and increased HA femoral head size compared to the contralateral femoral head (2.7 mm vs. 1.5 mm, p = 0.02) were associated with a significantly increased risk of conversion surgery. In the multivariate logistic regression, decreased age at index surgery, no dementia, use of a bipolar head, and increased leg length discrepancy (LLD) were associated with risk of conversion.

CONCLUSIONS

Patient characteristics, including younger age, increased BMI, and absence of dementia can lead to increased risk for conversion of HA to THA. Intraoperative considerations of head size and increase in ipsilateral LLD may increase the risk of conversion surgery. These factors should be considered by surgeons who employ HA for displaced FNFs.

Radiographic parameters associated with pain following total hip and surface arthroplasty

Pain following total hip arthroplasty (THA) and surface arthroplasty (SRA) remains a significant source of patient dissatisfaction. Two hundred twenty-four SRA and 196 THA patients completed a pain drawing questionnaire and postoperative radiographic measurements of component positioning were performed. In the SRA cohort, 11 of 21 patients (52%) with acetabular uncoverage of ≥5 mm versus 43 of 147 (29%) with acetabular uncoverage of ≤4.9 mm reported groin pain (P=.03). In the THA cohort, an increased distal-third canal fill ratio and a lower canal calcar ratio trended towards a higher incidence of thigh pain (P=.10 and .06), while a decreased mid-third canal fill ratio was associated with increased severity of thigh pain (P=.04). This study identifies associations between radiographic findings and pain following THA and SRA.

Measurement of leg length discrepancy after total hip arthroplasty. The reliability of a plain radiographic method compared to CT-scanogram

OBJECTIVE

To measure the interobserver reliability and intraobserver reproducibility of post total hip arthroplasty (THA) leg length discrepancy (LLD) measurement on radiographs as well as to evaluate its accuracy by comparing it with LLD measurement on computed tomographic scanogram (CT-scanogram).

MATERIALS AND METHODS

In this prospective study, postoperative LLD measurements in ten THA patients were made by four observers on anteroposterior radiographs of the pelvis (inter-teardrop line to the tip of lesser trochanter) and compared to LLD measurements made on CT-scanogram scout views of the lower limb. Two observers repeated the LLD measurements on radiographs 8 weeks after the first measurements. The interobserver reliability of the LLD measurement on plain radiographs was evaluated by comparing the measurements of the four observers and the intraobserver reproducibility by comparing the two repeated measurements made by the two observers.

RESULTS

We found excellent interobserver reliability (mean ICC 0.83) and intraobserver reproducibility (ICC 0.90 and 0.88) of the LLD measurements on plain radiographs. There was a moderate to excellent agreement, but with wide variation of measurements among the four observers, when plain radiographic measurement was compared with CT-scanogram (ICC 0.58, 0.60, 0.71, and 0.82).

CONCLUSION

Despite the excellent interobserver reliability and intraobserver reproducibility of LLD measurement on radiographs, clinicians should be aware of its limited accuracy when compared to CT-scanogram.

Influence of leg length discrepancy on clinical results after total hip arthroplasty--a prospective clinical trial

The effect of leg length differences on early clinical outcome after total hip arthroplasty remains uncertain. We performed a prospective study on 94 patients who were evaluated preoperatively and one year after surgery for clinical leg length differences, which were then compared with radiological measurements. The effect of leg length differences on walking ability, limp, pain and patient satisfaction was studied. The mean clinical leg length difference after operation was 0.05 cm (-1.5 to 1.5, SD 0.5). Clinical and radiological measurements correlated poorly (ω =0.36 pre- and ω =0.186 postoperatively). Patients with a shorter operated leg on clinical assessment were more prone to limping (p<0.05), and patients with a longer leg had more pain compared to patients with equal leg lengths (p<0.05). Walking ability, Harris Hip Score and patient satisfaction were only marginally affected by leg length differences. Virtually equal leg length was achieved for most patients but small differences had a negative influence in relation to limping and pain. Patients should be counselled pre-operatively about possible leg length differences and associated symptoms.

Residual groin pain at a minimum of two years after metal-on-metal THA with a twenty-eight-millimeter femoral head, THA with a large-diameter femoral head, and hip resurfacing

BACKGROUND

Groin pain may persist in up to 4.3% of patients after total hip arthroplasty and up to 18% of patients one year after hip resurfacing. The incidence of this problem after total hip arthroplasty with a large-diameter femoral head is unknown.

METHODS

We analyzed the natural history of groin pain and its clinical consequences during the first two years after three types of hip arthroplasty. Data were collected prospectively on 279 patients. Eighty-five patients had a polyethylene sandwich metal-on-metal total hip arthroplasty with a 28-mm-diameter femoral head, 105 had hip resurfacing, and eighty-nine had a total hip arthroplasty with a large-diameter femoral head component with three other cup designs (forty-nine in this group had the same monoblock acetabular cup design as those who had hip resurfacing).

RESULTS

At the twenty-four-month follow-up evaluation, seventy-seven patients (28%) reported at least one painful area around the hip and thirty-four patients (12.2%) had pain at more than one location. At three months, the incidence of groin discomfort was significantly increased in those who had hip resurfacing (30.5%) and in those who had total hip arthroplasty with a large-diameter femoral head (30%) compared with those who had total hip arthroplasty with a 28-mm femoral head (18.3%). This incidence decreased at two years (14.9%, 16.9%, and 12.9%, respectively). At twenty-four months postoperatively, eleven (four who had hip resurfacing, six who had total hip arthroplasty with the large-diameter head, and one who had total hip arthroplasty with the 28-mm head) of forty-one patients who had groin pain had not reported groin pain at previous follow-up evaluations. Of the forty-one patients reporting groin pain at the time of the last follow-up, twenty-three patients (56%) did not seek further evaluation or treatment, nine had revision surgery (22%), and the remaining nine patients thought the pain was substantial enough to warrant further evaluation and treatment.

CONCLUSIONS

When the exact source of groin pain cannot be found after total hip arthroplasty, careful follow-up should be done as local reactions to metal-on-metal implants and component loosening may take time to become apparent clinically or on imaging studies.

Distal lengthening of ilio-tibial band by Z-plasty for treating refractory greater trochanteric pain after total hip arthroplasty (Pedersen-Noor operation)

INTRODUCTION

The development of greater trochanteric pain (GTP) after total hip arthroplasty (THA) represents a special category. Despite that treatment is mainly conservative, some patients show poor response and surgical intervention should be considered. We propose a new method consisting of distal lengthening of ilio-tibial band (ITB) by Z-plasty.

MATERIAL AND METHODS

Between March 2004 and June 2006, 12 women with refractory GTP after THA were operated on using distal ITB lengthening. The procedure was done under local anaesthesia on an outpatient basis. The patients were followed up 3-4 months postoperatively by phone interview and at 1-3 years by EQ-5D questionnaire and clinical examination including tenderness evaluation with algometer.

RESULTS

All patients improved significantly (EQ-5D = 0.26 preoperatively vs. 0.67 postoperatively; P < 0.005) except one patient who experienced no change in GTP symptoms. No postoperative complications were reported.

CONCLUSION

We believe that treating patients with GTP after THA by the technique described offers a simple, safe and reliable method.

Leg length discrepancy in total hip arthroplasty: comparison of two methods of measurement

Measurement of leg length discrepancy is an important part in planning a successful total hip arthroplasty (THA). Many clinical and radiological methods with variable degrees of accuracy have been advocated to carry out this measurement. We studied the accuracy of a commonly used clinical method by comparing it to a well-known and reliable radiological method. A total of 139 patients aged 44-89 (mean: 67.5 years) scheduled to undergo THA were examined for clinical and radiological leg length discrepancy measurements before and after the operation by the same observers. There was a poor correlation between the clinical and radiological methods preoperatively [r = 0.21, intra-class correlation coefficient (ICC) = 0.33]. The correlation was better postoperatively (r = 0.45, ICC = 0.62). The clinical method used is not recommended for leg length discrepancy measurement preoperatively. Caution should even be taken when using this method postoperatively. The authors recommend using the radiological method when measuring leg length discrepancy as a part of planning for THA.