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1.

Purpose

A tapered straight cementless stem was used for revision in a group of old and very old patients. We wanted to know whether the use of this implant could achieve satisfactory results despite age and osteoporosis.

Methods

We retrospectively analysed data of 77 elderly patients (77 hips) who underwent revision in cemented and uncemented primary total hip arthroplasties (THA). The patients had a mean age of 82.2 years (range, 75–92 years) at revision surgery. They were monitored for a mean follow up of 7.1 years (range, 5.0–10.2 years). During the minimum follow-up period 11 patients died of unrelated causes, leaving 66 patients (66 hips) for evaluation.

Results

During the period of study three stems failed due to aseptic loosening, three hips dislocated and were successfully treated by closed reduction and bracing. No infection, osteolysis or significant stress shielding around the stems was observed. The survivorship at an average of 7.1-year follow-up was 95.5%.

Conclusions

These results indicate that this stem is an excellent alternative in revision THA in patients of 75 years or older.
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2.

Purpose

Femur deformities can make stem fixation difficult in total hip arthroplasty (THA). We report the clinical results of cementless THA using a press-fit stem in patients who had previously undergone femoral osteotomy for hip dysplasia.

Methods

The subjects included 66 hips in 64 patients, with the mean follow-up period of 7.3 years. THA was performed at a mean period of 17.1 years after intertrochanteric femoral osteotomy. Valgus osteotomy was performed in 42 hips, and varus osteotomy in 24. Clinical results were evaluated by using the Merle d’Aubigne-Postel score. Implant survival was determined with revision as the end point, and any related complications were investigated.

Results

The Merle d’Aubigne-Postel score improved from 9.4 to 16.1 at the final follow-up, without any implant loosening. However, periprosthetic femoral fractures were observed in four hips (6.0 %), one intra-operatively and three within three weeks after THA. Among these cases, three hips previously had varus osteotomy (12.5 %) and one hip had valgus osteotomy (2.3 %). Two hips were revised with full porous stems and circumferential wiring. The five and ten year cumulative survivorship rates were 97 % (range, 88.8–99.3 %) and 97 % (88.8–99.3 %), respectively.

Conclusions

Although the use of a press-fit cementless stem yielded acceptable results in most of the patients, perioperative femoral fracture was a major complication especially in the patients previously treated with intertrochanteric varus osteotomy. Careful planning and implant selection could be emphasized for these cases.
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3.

Purpose

The purpose of this study is to clarify morphological changes of acetabular subchondral bone cyst after total hip arthroplasty for osteoarthritis secondary to developmental dysplasia of the hip.

Methods

Two hundred and sixty-one primary cementless total hip arthroplasties of 208 patients, 18 males, 190 females, were retrospectively reviewed. Morphological changes of subchondral bone cyst were evaluated by computed tomography (CT). The mean cross-sectional area of the cyst from CT scans at 3 months postoperatively and after 7–10 years (average 8.4 years) were compared.

Results

Acetabular subchondral bone cysts were found in 49.0% of all cases in preoperative CT scans. There was no cyst which was newly recognized in CT scan performed after postoperative 7–10 years. All the cross-sectional areas of the cysts evaluated in this study were reduced postoperatively.

Conclusions

This study revealed that acetabular subchondral bone cysts do not increase or expand after total hip arthroplasty and indicated that the longitudinal morphological change of acetabular bone cysts in patients of developmental dysplasia of the hip do not influence long-term implant fixation in total hip arthroplasty.
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4.

Objective

Reconstruction/stable fixation of the acetabular columns to create an adequate periacetabular requirement for the implantation of a revision cup.

Indications

Displaced/nondisplaced fractures with involvement of the posterior column. Resulting instability of the cup in an adequate bone stock situation.

Contraindications

Periprosthetic acetabulum fractures with inadequate bone stock. Extended periacetabular defects with loss of anchorage options. Isolated periprosthetic fractures of the anterior column. Septic loosening.

Surgical technique

Dorsal approach. Dislocation of hip. Mechanical testing of inlaying acetabular cup. With unstable cup situation explantation of the cup, fracture fixation of acetabulum with dorsal double plate osteosynthesis along the posterior column. Cup revision. Hip joint reposition.

Postoperative management

Early mobilization; partial weight bearing for 12 weeks. Thrombosis prophylaxis. Clinical and radiological follow-ups.

Results

Periprosthetic acetabular fracture in 17 patients with 9 fractures after primary total hip replacement (THR), 8 after revision THR. Fractures: 12 due to trauma, 5 spontaneously; 7 anterior column fractures, 5 transverse fractures, 4 posterior column fractures, 1 two column fracture after hemiendoprosthesis. 5 type 1 fractures and 12 type 2 fractures. Operatively treated cases (10/17) received 3 reinforcement ring, 2 pedestal cup, 1 standard revision cup, cup-1 cage construct, 1 ventral plate osteosynthesis, 1 dorsal plate osteosynthesis, and 1 dorsal plate osteosynthesis plus cup revision (10-month Harris Hip Score 78 points). Radiological follow-up for 10 patients: consolidation of fractures without dislocation and a fixed acetabular cup. No revision surgeries during follow-up; 2 hip dislocations, 1 transient sciatic nerve palsy.
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5.

Introduction

Successful reconstruction during total hip arthroplasty for acetabular bone defects remains challenging. The purpose of our study was to evaluate clinical and radiographic results and performed a survivorship analysis for patients with acetabular bone loss undergoing total hip arthroplasty (THA) or revision THA using Kerboull-type acetabular reinforcement device(KT plate). Additionally, some independent prognostic factors for radiographic failure were identified.

Methods

A retrospective cohort study was conducted. Thirty patients (36 hips) were available for follow-up examination between 1997 and 2012, with a mean follow-up period of 10 years. We evaluated clinical and radiographic results. The mean patient age at the time of the operation was 66 years.

Results

Failure occurred in 6 cases, and further revisions were required for 2 hips. With failure for any reason as an endpoint, the cumulative survival at 10 years was 85%. Survival analysis at 10 years with failure as the endpoint revealed that the inclination angle of the KT plate ≤ 45° group showed higher survivorship than the inclination angle > 45° group (95.8 vs. 63.6%, P = 0.0047).

Conclusions

With a mean follow-up of 10 years, the clinical and radiographic outcomes were satisfactory. While this study group was small, the results suggest that prosthesis longevity may be improved by setting the inclination angle of this reinforcement device at ≤ 45°.
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6.

Objective

Treatment of displaced periprosthetic acetabular fractures in elderly patients. The goal is to stabilize an acetabular fracture independent of the fracture pattern, by inserting the custom-made roof-reinforcement plate and starting early postoperative full weight-bearing mobilization.

Indications

Acetabular fracture with or without previous hemi- or total hip arthroplasty.

Contraindications

Non-displaced acetabular fractures.

Surgical technique

Watson-Jones approach to provide accessibility to the anterior and supraacetabular part of the iliac bone. Angle-stable positioning of the roof-reinforcement plate without any fracture reduction. Cementing a polyethylene cup into the metal plate and restoring prosthetic femoral components.

Postoperative management

Full weight-bearing mobilization within the first 10 days after surgery. In cases of two column fractures, partial weight-bearing is recommended.

Results

Of 7 patients with periprosthetic acetabular fracture, 5 were available for follow-up at 3, 6, 6, 15, and 24 months postoperatively. No complications were recognized and all fractures showed bony consolidation. Early postoperative mobilization was started within the first 10 days. All patients except one reached their preinjury mobility level. This individual and novel implant is custom made for displaced acetabular and periprosthetic fractures in patients with osteopenic bone. It provides a hopeful benefit due to early full weight-bearing mobilization within the first 10 days after surgery.

Limitations

In case of largely destroyed supraacetabular bone or two-column fractures according to Letournel additional synthesis via an anterior approach might be necessary. In these cases partial weight bearing is recommended.
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7.

Background

Hemiarthroplasty (HA) is an effective procedure for treatment of femoral neck fracture. However, it is debatable whether unipolar or bipolar HA is the most suitable implant.

Objective

The purpose of this study was to compare the causes of failure and longevity in both types of HA.

Materials and methods

We retrospectively reviewed 133 cases that underwent revision surgery of HA between 2002 and 2012. The causes of revision surgery were identified and stratified into early (≤?5 years) failure and late (>?5 years) failure. Survival analyses were performed for each implant type.

Results

The common causes for revision were aseptic loosening (49.6%), infection (22.6%) and acetabular erosion (15.0%). Unipolar and bipolar HA were not different in causes for revision, but the unipolar group had a statistically significantly higher number of acetabular erosion events compared with the bipolar group (p?=?0.002). In the early period, 24 unipolar HA (52.9%) and 28 bipolar HA (34.1%) failed. There were no statistically significant differences in the numbers of revised HA in each period between the two groups (p?=?0.138). The median survival times in the unipolar and bipolar groups were 84.0?±?24.5 and 120.0?±?5.5 months, respectively. However, the survival times of both implants were not statistically significantly different.

Conclusions

Aseptic loosening was the most common reason for revision surgery after hemiarthroplasty surgery in early and late failures. Unipolar and bipolar hemiarthroplasty were not different in terms of causes of failure and survivorship except bipolar hemiarthroplasty had many fewer acetabular erosion events.
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8.

Background/purpose

In this study, cementless THA was performed for RA patients, and its clinical outcomes, as well as radiographic findings and implant survival rates, were examined more than 10 years after surgery in comparison with the outcomes of the same procedure performed for patients with hip osteoarthritis (OA) during the same period.

Method

We studied 28 cases of THA for RA clinically and radiologically at a minimum follow-up duration of 10 years. The patients consisted of 4 males and 22 females, with a mean age at the time of surgery of 53.1. The clinical and radiographic results were compared with an age-matched and sex-matched group of patients who had undergone THA for the diagnosis of primary or secondary OA.

Results

In the RA group, the mean Harris hip score was 48.3 before surgery, and improved to 76.8 at the time of the final survey. In the control group, the score also improved from 46.8 before to 86.5 after surgery, while revealing significant differences between the groups (p = 0.0002). In the RA group, 2 joints required revision THA on the acetabular side due to aseptic loosening, while such revision was not performed on the femoral side despite the presence of more than 2 mm of subsidence in 2 joints. The implant survival rate was 92.9 and 100 % in the RA and control groups, respectively, without significant differences (p = 0.493).

Conclusions

Although its clinical outcomes were significantly different from those for OA, a satisfactory implant survival rate was achieved, at 92.9 % in RA patients.
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9.

Background

Many different systems for the management of primary and secondary acetabular defects are available, each with its inherent advantages and disadvantages. The Revisio-System is a press-fit oval mono-block implant that makes a defect-oriented reconstruction and restoration of the center of rotation possible.

Material and methods

In this study, we retrospectively reviewed the outcome of 92 consecutive patients treated with this oval press-fit cup due to periacetabular bone loss. The average follow-up was 58.2 months. Defects were classified according to D’Antonio. There were 39 type II, 38 Type III, and 15 type IV defects. After an average of 4.9 years, the implant survival rate was 94.6% with cup revision as the end point and 89.1% with revision for any reason as the end point. The Harris Hip Score increased from 41.1 preoperatively to 62.3 postoperatively. The mean level of pain measured with the Visual Analogue Scale (VSA) was reduced from 6.9 preoperatively to 3.8 postoperatively.

Results

The Revisio-System represents a promising toolbox for defect-orientated reconstruction of acetabular bone loss in revision hip arthroplasty. Our results demonstrate that the implantation of the Revisio-System can result in a good mid-term clinical outcome.
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10.

Purpose

Hip fusion conversion has shown mixed results, in particular a higher rate of failure than primary total hip replacement. Conversion is usually carried out by a lateral approach.

Methods

We reported a series of 37 hip fusion conversions performed by an anterior approach. Clinical and radiographic outcomes of this unusual approach were reported at eight years of follow up.

Results

At eight years of follow up, survivorship was 86. 6 % (IC 95 %: 62.4–95.7 %). Sixteen patients reported good relief of the pre-operative back spine or knee pain. PMA score was significantly improved. Two implant aseptic loosenings needing revision surgery were reported.

Conclusion

The anterior approach seemed to be as good as the other hip approaches for hip fusion conversion to total hip replacement.
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11.

Background

Total hip replacement for high dislocation of the hip presents some difficulties, considering patients’ young ages, the abnormal hip anatomy and the high rate of complications. In this study, we present our experience in terms of clinical and radiological results in the treatment of Crowe type IV hips with subtrochanteric femoral shortening osteotomy and cementless total hip replacement.

Materials and Methods

We retrospectively reviewed 15 patients with Crowe type IV hip dysplasia (two bilateral cases for a total of 17 hips) treated with cementless total hip replacement associated with shortening subtrochanteric osteotomies (nine transversal and eight Z-shape osteotomies) between March 2000 to February 2006. The mean follow-up was 88 months (range 63–133). Harris hip score, leg length discrepancy, neurological status, union status of the osteotomy and the component stability were the criteria of the evaluation. All complications were noted.

Results

The mean HHS improved from 38.3 (range 32–52) to 85.6 (range 69–90). The mean preoperative leg length discrepancy was of 45 mm (range 38–70) and reduced to a mean of 12 mm (range 9–1.6) postoperatively. All osteotomies resulted healed at an average of 12.3 weeks (range 10–15). No cases of delayed union or nonunion were detected. Two patients (11%) showed early symptoms of sciatic nerve palsy which resolved uneventfully in 6 months. There was no migrations and none of the implants required revision.

Conclusions

Cementless THA with shortening subtrochanteric osteotomy is an effective method in the treatment of patients with Crowe type IV development dysplasia of the hip.

Level of evidence

IV.
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12.

Purpose

The aim of the present study was to evaluate the clinical and radiographic results of primary total hip arthroplasty (THA) performed with the Alloclassic Variall system (a modified version of the Alloclassic Zweymüller system) and to compare them with those in the literature for the original system.

Methods

Between January 2001 and December 2002, 273 consecutive primary THAs were performed in 259 patients at a single centre with the study system, using ceramic-on-ceramic (81.7 %) or ceramic-on-highly-crosslinked-polyethylene (18.3 %) articulations.

Results

At the time of this study, 28 patients (29 hips; 10.6 %) had died and 40 (43 hips; 15.8 %) were lost to follow-up. Seventeen patients (19 hips; 7.0 %) could be reached only by telephone. There were four revisions in four patients (1.5 %), all involving only the femoral component. Ten-year Kaplan-Meier survival with revision of any component for any reason as the endpoint was 98.4 % (95 % confidence interval: 96.9–100 %; 30 hips remained ‘at risk’). A total of 170 unrevised patients (178 hips; 65.2 %) were assessed clinically and radiographically at a median follow-up of 9.3 years (interquartile range [IQR] 8.8–9.8 years). The median Harris hip score (HHS) was 99.9 points (IQR 97.7–100). The score did not differ significantly between the two articulations. There was no sign of radiographic loosening.

Conclusions

The ten-year implant survival and the HHS score outcomes for THAs performed with the novel system were in line with those documented in the literature for its predecessor.
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13.

Background

Guidelines on the management of displaced intracapsular fractures recommend using an Orthopaedic Data Evaluation Panel-rated cemented implant. Prior to the National Institute for Health and Care Excellence guidelines, uncemented implants were commonly used in the UK.

Methods

We retrospectively examined the outcomes of patients with uncemented Thompson’s hemiarthroplasties at our unit, between April 2005 and December 2010. Patients who underwent revision surgery before December 2011 were identified. Implant survival calculation utilised the primary outcome of revision to total hip arthroplasty, revision hemiarthroplasty or excision arthroplasty. Patients who died post-operatively were identified and censored.

Results

A total of 1445 patients received uncemented Thompson’s implant. Patient mean age was 82 years with 76% female. Forty-six (3.2%) patients required revision with 15% performed within 30 days of surgery and 62% within 1 year. Reasons for revision were infection (0.83%), acetabular erosion (0.83%) and loosening (0.62%). Twenty-seven patients (59% of total revisions) underwent revision to THA, 14 (30%) to excision arthroplasty and 5 (11%) to revision hemiarthroplasty. Cumulative survival rate was 98% at 1 year and 95% at 5 years. Thirty-day mortality was 7.1%. One-year mortality was 28.1%.

Conclusion

Current guidelines strongly favour cemented hemiarthroplasty. Recognition that fractured hip patients are a non-homogeneous group is important. In patients with limited life expectancy, an uncemented Thompson is a quick, simple, palliative solution to early mobilisation. Correct surgical technique avoids using cement in this cohort, which is most vulnerable to bone cement implantation syndrome. Cost-effective resource utilisation with an increasingly elderly population remains a surgical responsibility.
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14.

Purpose

The aim of this study was to evaluate clinical and radiographic findings of stage 3 or lower osteonecrosis of the femoral head (ONFH) with intact acetabular cartilage in patients treated with bipolar hemiarthroplasty (BHA).

Methods

A total of 79 hips that underwent BHA for ONFH were included in this study. The average observation period was 7.6 years. Clinical results were evaluated using the Harris hip score. We performed radiographic analysis to assess the migration of the outer cup, the permanent image around the outer cup, and loosening of the stem.

Results

The total Harris hip score improved from 50 points before surgery to 92 points at final follow-up, while pain improved from 14 points to 36 points. Flexion improved from 94° to 120° and abduction from 27° to 37°. One patient on dialysis showed progress in terms of inward migration, and revision surgery was performed on the patient 14 years after the original surgery.

Conclusions

Midterm performance of BHA for stage 3 or lower ONFH at our hospital was good.
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15.
16.

Background

The results after acetabular component revision are very heterogeneous, irrespective of the use of established or new components. This could be due to a lack of treatment standards for new revision components. The Trabecular Metal? (TM) revision system, through its modularity, allows for an individual intraoperative reconstruction of the acetabular defect with a single implant system. It was the aim of this study to investigate the results of acetabular revision with the TMT system taking into consideration the utilized components and the acetabular defect.

Methods

A total of 200 consecutive isolated revisions of the acetabular component from 2010 until 2012 were retrospectively analyzed from our institutional database. Of the 200 cases, 114 revisions were performed with a combination of different TMT components (wedge and cup, cup and cage). Aseptic cup failure and revision for any reason were the defined endpoints of this study. The acetabular defects were graded according to the Paprosky classification.

Results

The average patient age was 63.6 ± 14.8 years (range 32–85 years) and the average follow-up was 5.3 ± 0.7 years. The overall revision rate, independent of the utilized components, was 4.4% and the revision rate for aseptic failure of the acetabular component was 2.6%. The revision rate for aseptic loosening for Paprosky type I and II defects was 0% and Paprosky type III and IV defects was 12%.

Conclusions

The modular TMT system shows low revision rates. The modularity of the system allows for a safe and intraoperative adaptation to the individual acetabular defect without the need for extensive preoperative imaging or custom-made implants.
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17.

Purpose

Revision surgery for a patient with previous recurrent dislocations or abductor muscle dysfunction has been considered to be a complication-prone procedure regardless of the type of constrained implant used. We investigated the survivorship of a focally constrained acetabular liner used for revision total hip arthroplasty in patients with abductor insufficiency or previous recurrent dislocations.

Methods

We retrospectively reviewed 98 patients in whom a focally constrained acetabular liner was used to treat abductor insufficiency or previous recurrent dislocations. The mean age was 69.4 years (37–92) and 64 of these were females. Previously, the patients had undergone a mean of two (1–5) revisions. The mean follow-up was 38 (12–66) months. Kaplan-Meier survival curves were calculated and Log-rank test was used to test the difference in survivorship between patients with abductor insufficiency and previous dislocations.

Results

Sixteen patients needed a further re-revision for any cause. Thus, the revision-free survivorship was 84.3 % at five years. Five patients suffered a dislocation with a mean of five months post-operatively and were managed with repeat revision. Five patients failed at the implant-host bone interface. Three of these failures occurred after cementing the constrained liner into a pre-existing shell.

Conclusions

The focally constrained liner provided a reasonable option for revision total hip arthroplasty in patients with hip instability. Failures were observed in patients with acetabular osteolysis but seemingly well-fixed component and unrecognized impingement.
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18.

Background

Displaced fractures of the acetabulum involving the quadrilateral plate continue to be a surgical challenge. In this study, we describe our operation technique of auxiliary acetabular cerclage-wiring combined with plate osteosynthesis and present our results as well as short-term outcome.

Patients and methods

All patients aged 18 years and older treated with auxiliary cerclage-wiring between 2007 and 2012 were included in this study. Fractures were classified according to Letournel. Cerclage wiring was used when reposition and retention of the fracture was insufficient with plates and screws alone. Short-term outcome was evaluated by the German Short Musculoskeletal Functional Assessment (SMFA-D) questionnaire.

Results

Data from 23 patients were collected. The follow-up period was 7 months (range 2–23 months). Of the 23 patients, 22 showed excellent fracture reduction and retention. One patient had to undergo revision surgery due to loss of reposition. Patients showed good functional outcome.

Conclusion

Auxiliary acetabular cerclage-wiring is a safe and effective method for fracture reduction and retention especially in displaced acetabular fractures involving the quadrilateral plate.
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19.

Purpose

Dislocation is a leading cause of failure after revision total hip arthroplasty (THA). This study was conducted to examine the risk factors for dislocation as well as their recurrence after revision THA.

Methods

We retrospectively reviewed 178 revision THAs in 162 patients between 1998 and 2013. The mean patient age was 65.2 years at operation and the mean follow-up period was 6.7 years. Multivariate logistic regression was performed to identify risk factors for dislocation, and further comparison was made between patients with single and recurrent dislocations.

Results

Sixteen hips in 15 patients (9.0 %) dislocated at a mean of 9.1 months (range, 0–83 months) after revision THA. Multivariate analysis identified advanced age (odds ratio [OR]?=?2.94/10 years) and osteonecrosis of the femoral head (OR?=?7.71) as the independent risk factors for any dislocations. Risk factors for recurrent dislocations, which were observed in eight hips (50 %), were later dislocations (≥4 months) and lower BMI.

Conclusion

Dislocation is a serious problem after revision THA with multiple risk factors. Although our findings were limited to revision THAs done through posterolateral approach, recognition of these factors is helpful in patient education and surgical planning.
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20.

Background

Short stem cementless femoral components were developed to aid insertion through smaller incisions, preserve metaphyseal bone, and potentially decrease or limit the incidence of thigh pain. Despite some clinical success, the senior author (DDG) believed a higher percentage of his patients who had received a cementless short stem design were experiencing thigh pain, which, coupled with concerns about bone ingrowth fixation, motivated the review of this case series.

Questions/purposes

(1) What is the proportion of patients treated with a short stem cementless THA femoral component that develop thigh pain and what are the hip scores of this population? (2) What are the radiographic results, specifically with respect to bone ingrowth fixation and stress shielding, of this design? (3) Are there particular patient or procedural factors that are associated with thigh pain with this short stem design?

Methods

Two hundred sixty-one primary THAs were performed in 238 patients by one surgeon between November 2010 and August 2012. During this time period, all patients undergoing primary THA by this surgeon received the same cementless short titanium taper stem. Seven patients (eight hips) died and five patients (five hips) were lost to followup, leaving 226 patients (248 hips) with a mean followup of 3 years (range, 2–5 years). Patients rated their thigh pain during activity or rest at final followup on a 10-point visual analog scale. Harris hip scores (HHS) were obtained at every clinic appointment. Thigh pain was evaluated at the final followup or by contacting the patient by phone. Radiographs were evaluated for bone-implant fixation, bone remodeling, and osteolysis. An attempt was made to correlate thigh pain with patient demographics, implant specifications, or radiographic findings.

Results

Seventy-six percent of hips (180 of 238) had no thigh pain, 16% of hips (37 of 238) had mild thigh pain, and 9% (21 of 238) had moderate or severe thigh pain. Preoperatively, mean HHS was 47 (SD, 16) and at last followup, mean HHS was 88 (SD, 13). There were two femoral revisions, one for severe thigh pain and the other for infection. All but two components demonstrated bone ingrowth fixation (99%). Femoral stress shielding was mild in 64% of hips (135 of 212), moderate in 0.5% (one of 212), and severe in no hips. There is an inverse linear relationship between age and severity of thigh pain (r = ?0.196; p < 0.0024).

Conclusions

Although reliable fixation was achieved and good HHS were attained, the frequency and severity of thigh pain with this short cementless stem were concerning. The surgeon has subsequently abandoned this short stem design and returned to a conventional length stem. Future study direction might investigate the biomechanical grounds for the thigh pain associated with this stem design.

Level of Evidence

Level IV, therapeutic study.
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