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

Risk Factors for Trochanteric Bursitis Following Total Hip Arthroplasty: A Radiographic Analysis

BACKGROUND

Trochanteric bursitis (TB) is a prevalent complication following total hip arthroplasty (THA), with increased offset hypothesized as a potential risk factor. This study investigated potential TB predictors in THA patients, including radiographic measurements of offset and leg length, comorbidities, and patient characteristics.

METHODS

In this retrospective cohort study, all THA patients from a single academic tertiary care center between 2005 and 2021 were reviewed. Exclusion criteria included less than one-year follow-up, osteonecrosis, or fracture. Manual radiographic measurements of offset (acetabular, femoral, and total) and leg length from preoperative and postoperative AP (antero-posterior) pelvis X-rays were taken, with scaling using femoral cortical diameter. Univariable and multivariable Cox proportional hazard models were employed to estimate TB risk.

RESULTS

Of 1,094 patients, 103 (9.4%) developed trochanteric bursitis, with a median (Q1, Q3) time to presentation of 41.8 weeks (25.5, 66.9). In univariable models, only sex was associated with increased TB risk, with women exhibiting a 1.79 times increased risk (HR [hazard ratio]: 1.79 (1.16, 2.76), P = 0.009). Changes in acetabular offset, femoral offset, total offset, and leg length between preoperative and postoperative radiographs were not associated with an increased risk of developing TB in the univariate or multivariate models. Furthermore, various offset thresholds were evaluated, with no amount of increased offset showing increased TB risk.

CONCLUSION

This study found no relationship between femoral, acetabular, or total offset and trochanteric bursitis following THA. These findings suggest that surgeons may consider adding offset for increased prosthetic stability in high-risk cases. However, given that this is a retrospective study, the authors are not advocating for the routine use of increased offset. The study identified women as a risk factor with a 1.79 times higher TB risk, highlighting the importance of counseling women patients on this heightened risk.

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.

Restoration of hip anatomy using computer modelling prior to total hip arthroplasty and its potential consequences in terms of lower limb-length difference

BACKGROUND

Restoring hip anatomy during total hip arthroplasty (THA) is the gold standard. The general goal is for hips to be symmetrical in terms of height. This study aimed to analyse the effect of simulating hip length (HL) equalisation on leg-length difference (LLD) before and after THA with a computerised plan.

METHODS

141 consecutive patients were enrolled following THA. Outcomes of interest were preoperative hip-length difference (HLD) and LLD as determined on CT and final LLD as determined by simulating HL equalisation. We divided patients into 3 groups: no LLD, LLD >5 mm and LLD ⩾10 mm.

RESULTS

The rate of preoperative LLD >5 mm and LLD ⩾10 mm was 37.5% and 14.8%, respectively. HL equalisation did not change LLD distribution in the overall cohort. Among patients with smaller preoperative HLs and LLDs, HL equalisation changed the rate of LLD >5 mm from 100% (n = 24) to 41.7% (n = 10) (p < 0.0001) and of LLD ⩾10 mm from 100% (n = 12) to 16.7% (n = 2) (p < 0.0001). Among patients with no preoperative LLD, HL equalisation changed the rate of LLD ⩽5 mm from 100% (n = 64) to 59.3% (n = 38) (p < 0.0001) and of LLD<10 mm from 100% (n = 76) to 89.5% (n = 68) (p = 0.006).

CONCLUSIONS

Restoring biomechanical hip anatomy by HL equalisation may not be the correct goal for all patients. In patients with no LLD and shorter HLs, equalisation could result in LLD >5 mm in 40% of patients and LLD >10 mm in 10%, demonstrating the necessity to further analyse individuals and propose a personalised stem position.

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.

Does Body Mass Index (BMI) Affect the Reconstruction of Biomechanical Parameters in Patients Undergoing Total Hip Replacement (THR) through the Direct Anterior Approach (DAA)?

OBJECTIVE

Direct anterior approach total hip replacement (DAA-THR) is gaining increased interest due to its tissue-sparing nature and rapid recovery. Obesity has been shown to be a significant parameter influencing cup positioning in DAA-THR. It was the intention of this retrospective study to examine how obesity would influence the restoration of native hip biomechanical parameters during DAA-THR.

MATERIALS AND METHODS

A total of 74 patients from a high-volume university orthopedic center after unilateral DAA-THA were included. Patients were retrospectively allocated to a study group (BMI > 30 kg/m2) and a control group (BMI < 30 kg/m2). Furthermore, propensity-score matching for baseline parameters was performed, leaving 30 patients in each group. Biomechanical parameters of the hip (i.e., femoral offset (FO), abductor lever arm (ABL), acetabular offset (AO), center of rotation (COR), stem alignment (SA), body weight lever arm (BWL), cup inclination (CI), and leg length discrepancy (LLD) were evaluated on standardized plain radiographs, and parameters were compared to the native contralateral hip.

RESULTS

Mean BMI in the study group was 35.07 ± 5.13 kg/m2 and 25.43 ± 2.64 kg/m2 in the control group. There was a significant decrease of the ABL only in the study cohort (p = 0.01). CI and SA did not differ between both cohorts. FO was slightly increased compared to the native hip in both groups. There was a marginally higher but non-significant proportion of improper FO restoration in the study group (19 vs. 16 patients, p = 0.60).

CONCLUSIONS

Obesity, as quantified by BMI, only has a limited impact on the adequate reconstruction of native biomechanical parameters of the hip during DAA-THR. ABL was the only parameter to be significantly decreased in the overweight patients after DAA-THR. Therefore, special care should be taken on proper acetabular reaming and consequent seating of the cup in the obese patient to avoid excessive lateral positioning.

Accuracy of Preoperative 3D vs 2D Digital Templating for Cementless Total Hip Arthroplasty Using a Direct Anterior Approach

Background

An important aspect of preoperative planning for total hip arthroplasty is templating. Although two-dimensional (2D) templating remains the gold standard, computerized tomography (CT)-based three-dimensional (3D) templating is a novel preoperative planning technique. This study aims to compare the accuracy of a 2D and 3D plan using an anterior approach for the placement of the same uncemented prosthesis.

Methods

Two consecutive cohorts of 100 patients each were retrospectively analyzed. We analyzed the accuracy of the size of the implant (stem, cup, head), the length of head, and offset. As a secondary criterion, we analyzed the rates of stems with more than 3° of varus, fracture, and/or subsidence at 3 months postoperatively.

Results

Within the exact size, the accuracy of the stem and cup size with the 2D plan was 69% and 56%, respectively. With the 3D plan accuracy being 88% (P = .0046) and 96% (P < .0001), respectively. Regarding size and length of the implant head, accuracy was 86% and 82% with the 2D plan and 100% (P < .0001) and 94% (P = .016), respectively, with the 3D plan. The offset of the implants increased beyond 3 mm in 23% of patients in the 2D group and in 5% of patients in the 3D group (P = .0003). The rate of varus stems was 10% in the 2D group and 2% in the 3D group (P = .03). Two fractures and one case of subsidence occurred in the 2D group. None were identified in the 3D cohort.

Conclusions

A CT-based 3D plan is more accurate for implant size selection, allows better prosthetic offset, and reduces the rate of varus stems.

Fluoroscopy-guided direct anterior approach total hip arthroplasty provides more accurate component positions in the supine position than in the lateral position

PURPOSE

The position of the acetabular and femoral components is critical for stability and wear resistance. The aim of this study is to investigate whether the fluoroscopy-guided direct anterior approach in the supine position (S-DAA) is more helpful in improving the position of acetabular and femoral components than the fluoroscopy-guided direct anterior approach in the lateral decubitus position (L-DAA).

METHODS

A retrospective analysis of 76 cases of fluoroscopy-guided direct anterior approach total hip arthroplasty (38 cases in the S-DAA and 38 cases in the L-DAA group) was performed in one hospital from 2019 to 2021. The differences in inclination, anteversion, femoral offset (FO), global offset (GO), and leg length discrepancy (LLD) measurements during and after surgery were analyzed. The postoperative femoral offset (FO), global offset (GO), leg length discrepancy (LLD), and preoperative and postoperative Harris hip score were compared between the two groups.

RESULTS

In the S-DAA group, there were no significant differences in the mean intraoperative inclination angle anteversion angle, FO, GO, and LLD compared to the postoperative values, whereas in the L-DAA group, there were significant differences between the intraoperative and postoperative measurements (P < 0.001, P = 0.009, P＜0.001, P＜0.001 and P = 0.008, respectively). Additionally, there were significant differences in the accuracy of LLD, FO, and GO between the two groups (P < 0.001). Compared with the L-DAA group, the average differences of inclination, anteversion, LLD, FO, and GO during and after operation in the S-DAA group were smaller, and the consistency was higher. There was a significant difference in Harris hip score between the two groups at 1 week after surgery (P = 0.033). There was no significant difference in Harris hip score between 1 month and 3 months after surgery (P = 0.482 and P = 0.797, respectively).

CONCLUSIONS

In the supine group, the direct anterior approach (DAA) provides more accurate positioning of the acetabular and femoral components. However, there was no significant difference in hip joint function and activity between the two groups at follow-up.

The Anterior Position of the Hip Center of Rotation Is Related to Anterior Cup Protrusion Length and Symptomatic Iliopsoas Impingement in Primary Total Hip Arthroplasty

BACKGROUND

Iliopsoas impingement (IPI) is an important complication after total hip arthroplasty (THA), and anterior cup protrusion is believed to be its main cause; however, the relationship between the hip center of rotation (COR) and symptomatic IPI or cup protrusion remains poorly understood. Therefore, the present study investigated these relationships.

METHODS

The medical records of 138 patients who underwent unilateral primary THA were retrospectively reviewed. There were 8 patients (5.8%) who had symptomatic IPI. The COR and cup protrusion length measured with 2 methods were assessed on computed tomography. Risk factors for symptomatic IPI and the relationship between the COR and protrusion length were evaluated.

RESULTS

Logistic regression analyses showed that anteroposterior position of the COR, sagittal cup protrusion length (SCPL) at the COR, and both axial and SCPLs at the most anterior margin of the cup were related to symptomatic IPI. Multivariable regression analyses showed that acetabular offset was related to axial protrusion length at the COR, and anteroposterior position of the COR was related to both axial and sagittal protrusion lengths at the most anterior margin of the cup.

CONCLUSION

Anterior position of the cup was related to symptomatic IPI and both axial and sagittal protrusion lengths at the most anterior margin of the cup. Anterior reaming and cup protrusion should be avoided as much as possible to prevent symptomatic IPI.

The Role of Global Femoral Offset in Total Hip Arthroplasty with High Hip Center Technique

OBJECTIVE

The high hip center (HHC) technique has been proposed for the treatment of patients with developmental dysplaisa of the hip (DDH) who have an acetabular bone defect. However, the importance of global femoral offset (FO) in the application of this technique has not been sufficiently appreciated. Our goals were to confirm that the HHC technique is feasible in the treatment of patients with DDH and to assess the function of global FO in this procedure.

METHODS

We retrospectively analyzed 73 patients who underwent total hip arthroplasty using high hip center technique for unilateral DDH at our hospital between January 2014 and June 2019. According to global FO, the patients were split into three groups: increased FO group (increment greater than 5 mm), restored FO group (restoration within 5 mm) and decreased FO group (reduction greater than 5 mm). Patients' medical records and plain radiographs were reviewed. One-way ANOVA was used to compare radiographic outcomes and Harris hip score (HHS). Paired t-test was used to assess preoperative and postoperative HHS and leg length discrepancy. Trochanteric pain syndrome, Trendelenburg sign and postoperative limp was evaluated with Fisher's exact test.

RESULTS

The average follow-up time was 7.5 ± 1.4 years. The patients' HHS and leg length discrepancy were significantly improved (p < 0.05). In terms of vertical acetabular height, abductor arm, postoperative leg length difference, and acetabular cup inclination, there was no statistically significant difference between the three groups. At the last follow-up, HHS was significantly higher in the restored FO group than in the decreased FO and increased FO groups. Trochanteric pain syndrome occurred in 15.0% and Trendelenburg sign and postoperative limp in 8.2% of all patients, respectively. Trochanteric pain syndrome, Trendelenburg sign and postoperative limp did not differ significantly across the three groups. One patient in increased FO group underwent revision for dislocation 6 years after surgery.

CONCLUSION

The HHC technique is an alternative technique for total hip arthroplasty in patients with acetabular bone abnormalities, according to the results of the mid-term follow-up. Also, controlling the correction of the global femoral offset to within 5 mm may lead to better clinical outcomes.

The modern state of femoral, acetabular, and global offsets in total hip arthroplasty: a narrative review

Offsets in the frontal plane are important for hip function. Research on total hip arthroplasty (THA) surgery agrees that increasing femoral offset up to 5 mm could improve functional outcome measures. The literature indicates that global offset is a key parameter that physicians should restore within 5 mm during surgery and avoid decreasing. Substantiated findings on acetabular offset are lacking despite its recognized importance, and the medialization approach must be assessed in light of its shortcomings. Future research, possibly through improved measurement, unified definitions, patient-specific surgical planning, and technology-enhanced surgical control, with specific focus on acetabular offset, is needed to better understand its impact on THA outcomes.

[Standard and special liner in primary hip arthroplasty : Current study and survey results from the German Arthroplasty Registry (EPRD)]

BACKGROUND

Instability constitutes the main reason for revision hip arthroplasties. Modified polyethylene liners are designed to improve the stability of a hip replacement. In July 2022 The Bone & Joint Journal published a study with data of the German Arthroplasty Registry (EPRD). The study investigated mechanical failure of standard and modified liner designs in primary, cementless total hip arthroplasty. Following the study, the EPRD conducted a survey of German clinics to research the utilization of lipped liners in primary total hip replacement.

METHODS

The liner study included 151,096 primary, elective, cementless total hip arthroplasties. Data from November 2012 to November 2020 were obtained from the EPRD. Standard polyethylene liners were compared with lipped, angulated, offset and angulated/offset inlays. Cumulative incidences for endpoint revision due to mechanical complication were calculated with a competing risk analysis. The influence of other variables was investigated with a multivariate Cox regression. In the following online survey, 237 out of 789 hospitals completed a form.

RESULTS AND CONCLUSION

In our analysis, only offset liners were, compared to standard liners, associated with a reduced risk of mechanical failure in a short to medium follow up. However, the resultant joint reaction force is increased with offset liners due to the lateralization of the hip center of rotation. Thus, the long-term performance of offset liners needs to be observed. Our survey indicated that lipped liners were implanted more often if the posterior approach was used. Moreover, lipped liners were mostly positioned with the elevated rim in the biomechanically less optimal posterior-superior quadrant. To improve stability it is suggested to position the elevated rim in the posterior-inferior quadrant.

Prospective randomized controlled trial on the accuracy of prosthesis positioning in total hip arthroplasty assisted by a newly designed whole-process robotic arm

INTRODUCTION

The purpose of this article is to study whether the newly designed whole-process total hip arthroplasty (THA) robotic arm can improve the accuracy of prosthesis placement in THA.

METHOD

In this study, 72 patients undergoing THA were prospectively included and randomly divided into two groups. The experimental group was treated with THA assisted by a newly designed robotic arm. The control group received THA with conventional surgical methods. The imaging data were compared after operation.

RESULT

Compared with the conventional operation, the whole-process robotic arm can more accurately place the acetabular prosthesis in the anteversion safe zone of 5 ~ 25°, but in terms of the inclination angle, whether the reference is the safe zone of 30 ~ 50° or 30 ~ 45°, there is no statistical difference between the two groups. The average lower limb length discrepancy (LLLD) in the experimental group was 3.77 ± 8.31 mm longer than contralateral side, while the counterpart in the control group was 8.39 ± 9.11 mm, with significant difference (P = 0.029). The femoral prosthesis was fixed in neutral position in 35 (100%) cases in the experimental group and only 30 (83.3%) in the control group (P = 0.036). There was no significant difference in the recovery of hip offset, femoral anteversion, and canal fill ratio (CFR) between the two groups.

CONCLUSION

Robotic arm can improve the accuracy of anteversion of acetabular cup, restore the consistency of the length of lower limbs, and more accurately implant the femoral prosthesis to the neutral position in the coronal position.

CLINICAL TRIAL REGISTRATION NUMBER

ChiCTR2100044124 (date of registration: 2021-3-11).

The association of postoperative global femoral offset with total hip arthroplasty outcomes

Global femoral offset (GFO) and femoral offset (FO) reportedly affect outcomes following total hip arthroplasty (THA). However, FO assessed using plain radiography is affected by internal and external rotations of the hip joint. We investigated the relationship between leg length discrepancy and Harris hip score (HHS), and their influence on acetabular offset (AO), FO, GFO, anterior femoral offset, and outcomes after THA. We retrospectively evaluated 140 patients with hip osteoarthritis who underwent THA. A three-dimensional (3D) pelvis and femur model created from computed tomography (data using ZedHip software was used to investigate these parameters. The modified (m)HHS scores were significantly improved from 49.0 to 88.8 in total mHHS, 20.0-44.5 in pain, and 28.9-44.4 points in function. Significant correlations were found between the differences in AO, FO, GFO, and pain score in binominal, with maximum values of - 1.24, + 1.54, and + 0.90 mm/100 cm body height, respectively. The maximum value of GFO and mHHS in binominal was + 1.17 mm/100 cm body height (BH). The optimal range of difference of GFO was - 1.75 to 4.09 mm/100 cm BH. This is the first report using a 3D method for assessing FO. Preoperative planning using the system could improve postoperative function.

Radiologic restoration inaccuracy increases postoperative dislocation in primary total hip arthroplasty: a retrospective study with propensity score matching

BACKGROUND

Dislocation is a complicated process and associated with multivariate etiology and risk factors. The purpose of this study was to verify if radiologic restoration inaccuracy increases postoperative dislocation in primary total hip arthroplasty (THA) individually or synergistically.

METHODS

From 2017 to 2020, we identified 76 (1.9%) patients who suffered postoperative dislocations from 3926 THAs in our institution. After excluded patients with previously proven patient-related and implant-related risk factors, the remaining patients were used to match a 1:1 control patients who were without dislocation. The cup position (inclination and anteversion angles), hip offset (HO), leg length discrepancy (LLD), and abductor lever arm (ALA) were analyzed by univariate analyses and multivariate logistic regressions.

RESULTS

Measurements on radiographs showed excellent interobserver agreement (intraclass correlation coefficient (ICC) 0.922-0.952) and intraobserver agreements (ICC 0.933-0.967). HO restoration inaccuracy (without ± 5 mm) was associated with higher dislocation risk (OR 4.241 95% CI 1.440-12.492, P = 0.009). The restoration inaccuracy of the cup position, LLD, or ALA could not increase the dislocation risk individually. When combining the radiologic restoration inaccuracy factors, the HO + LLD restoration inaccuracy and HO + ALA restoration inaccuracy increased the odds of postoperative dislocation (OR 12.056, 95% CI 1.409-103.127, P = 0.023; OR 4.770, 95% CI 1.336-17.028, P = 0.016, respectively). Combining the four risk factors of cup safe zone, HO, LLD, and ALA, patients with 3 or 4 radiologic restoration inaccuracy factors showed a higher risk of dislocation (OR 13.500, 95% CI 1.340-135.983, P = 0.027).

CONCLUSION

Hip offset (HO) restoration inaccuracy increased the risk of dislocation following primary THA. Multivariate radiologic restoration accuracy is critical for the prevention of dislocation and needs to be valued by surgeons.

Supine versus lateral position for total hip replacement: accuracy of biomechanical reconstruction

BACKGROUND

Restoration of normal hip anatomy and biomechanics is a key surgical goal for success in total hip arthroplasty. The aim of this study was to evaluate the influence, if any, that patient positioning in the supine and lateral decubitus positions has in achieving this goal.

MATERIALS AND METHODS

A single center multi-surgeon case-matched series from a tertiary level referral center of patients undergoing primary unilateral THA for osteoarthritis between April 2018 and December 2019 was retrospectively analyzed. Patients (n = 200) were divided into two matched groups: supine (anterior approach, n = 100) and lateral decubitus (direct lateral or posterior/SuperPATH™ approaches, n = 100). Post-operative anteroposterior pelvic radiographs were analyzed using a previously validated software (SurgiMap, Nemaris Inc., USA) for parameters of reconstruction of the hip in the coronal plane; leg length discrepancy, vertical and horizontal displacement of the center of rotation, femoral offset, and total offset.

RESULTS

Mean absolute leg length discrepancy in the supine group was 0.6 ± 3.3 mm (95% [CI] - 0.1 to 1.2 mm) versus 2.4 ± 3.8 mm (95% [CI] 1.6 to 3.1) in the lateral decubitus position (p < 0.001). The center of rotation was displaced medially by a mean of 3.2 ± 2.7 mm in the supine group versus 1.3 ± 4.0 mm in the lateral decubitus group (p < 0.001). For a surgical target of reconstructing both leg length and total offset within 5 mm of native anatomy, the supine group was more than twice as likely to achieve these goals with fewer outliers (OR 2.631, 95% [CI] 1.901-3.643) (76% v 30%, p < 0.001).

CONCLUSION

Total hip arthroplasty through the anterior approach in the supine position is more consistent and accurate for the restoration of leg length and total offset. Further study is required to assess how this translates with outcome.

LEVEL OF EVIDENCE

III-retrospective cohort study.

Tendinopathies and Allied Disorders of the Hip

There are many soft tissue structures around the hip joint that may serve as a source of pain in both the native and prosthetic hip. In this review, the role of the gluteal, piriformis, iliopsoas, and rectus femoris musculotendinous units in the etiology of pathology around the hip joint will be discussed. Management options ranging from tailored physical therapy regimens to local steroid infiltration along with more invasive open and arthroscopic surgical techniques will be reviewed for each pathological entity. While not all conditions are well understood, advancements have been made in the management of each of these often challenging cases in both the native and prosthetic hip settings. This review explores these advancing treatment methods which will supplement the practice of any hip surgeon who is presented with problematic tendinopathy around both the native and prosthetic hip joint.

THA with Use of Patient-Specific Resurfacing Jigs and a Novel Customized Implant Design

»

Conventional total hip arthroplasty (THA) largely remains an unguided procedure dependent on the ability and experience of the surgeon. New technologies, such as patient-specific instrumentation and robotics, have shown promising results in improving implant positioning, which has the potential to improve patient outcomes.

»

The use of off-the-shelf (OTS) implant designs, however, limits the success of the technological advances since they are unable to recreate the native anatomy of the joint. The inability to restore femoral offset and version or the presence of implant-related leg-length discrepancies often lead to suboptimal surgical results that increase the risk of dislocation, fractures, and component wear, compromising postoperative functional outcomes and implant longevity.

»

A customized THA system, whereby the femoral stem is designed to restore patient anatomy, has recently been introduced. The THA system uses computed tomography (CT)-derived 3D imaging to create a custom stem, patient-specific component placement, and patient-specific instrumentation that matches the patient's native anatomy.

»

The purpose of this article is to provide information on the design and manufacturing process of this new THA implant, to illustrate the associated preoperative planning, and to describe the surgical technique; 3 surgical cases are presented.

Clinical and radiological results of high offset tri-lock bone preservation stem in unilateral primary total hip arthroplasty at a minimum follow-up of 3 years

Background

Although the high offset Tri-Lock bone preservation stem (BPS) was used widely, few studies explored the clinical and radiological results. The purpose of this study was to determine the clinical and radiological results of high offset Tri-Lock BPS in unilateral primary total hip arthroplasty (THA) at a minimum follow-up of 3 years.

Methods

55 patients who underwent cementless THA with high offset Tri-lock BPS from 2017 to 2018 were followed for a minimum follow-up of 3 years. Patients were assessed clinically for complications, Harris hip score (HHS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Oxford Hip Score (OHS). Femoral offset (FO), acetabular offset (AO), hip offset (HO), HO difference, and leg length discrepancy (LLD) were measured on the anteroposterior (AP) pelvic radiograph. Standard pelvic AP and lateral radiographs were used to evaluate for evidence of bone ingrowth, stem subsidence, stem alignment, radiolucent line around the stem, osteolysis, loosening, ectopic ossification, and femoral stress shielding.

Results

No patients reported complications during hospitalization nor the follow-up period. At a mean follow-up of 42.5 months, the mean HHS, WOMAC, and OHS scores showed a significant improvement from preoperative to the latest follow-up. No patients reported thigh pain. No revision nor sign of radiographic loosening had been detected. The high offset Tri-Lock BPS significantly improved the FO and HO postoperatively. HO difference and LLD were balanced postoperatively. No sign of stem subsidence, radiolucent line, osteolysis, loosening, ectopic ossification, nor severe stress shielding (more than grade 3–4) were observed at the latest follow-up.

Conclusion

The high offset Tri-Lock BPS demonstrated excellent clinical and radiographic outcomes at a minimum follow-up of 3 years. HO difference and LLD between legs decreased significantly and achieved balance postoperatively. Long-term follow-up is required for a definitive conclusion.

Platelet-rich plasma versus steroids injections for greater trochanter pain syndrome: a systematic review and meta-analysis

INTRODUCTION

Greater trochanter pain syndrome (GTPS) is characterized by a persistent and debilitating pain around the greater trochanter. GTPS can be caused by a combination of gluteus medius or minimus tendinopathy, snapping hip or trochanteric bursitis.

SOURCE OF DATA

Recent published literatures identified from PubMed, EMBASE, Google Scholar, Scopus.

AREAS OF AGREEMENT

Platelet rich plasma (PRP) and corticosteroids (CCS) injections are useful options to manage symptoms of GTPS.

AREAS OF CONTROVERSY

Whether PRP leads to superior outcomes compared to CCS injections is unclear.

GROWING POINTS

A systematic review and meta-analysis comparing PRP versus CCS in the management of GTPS was conducted.

AREAS TIMELY FOR DEVELOPING RESEARCH

PRP injections are more effective than CCS at approximately 2 years follow-up.