Long-Term Results of Alumina Ceramic-On-Ceramic Bearings in Cementless Total Hip Arthroplasty: A 20-Year Minimum Follow-Up.

BACKGROUND: Alumina ceramic-on-ceramic bearings are used in total hip arthroplasty (THA) because of their wear-resistant and inert properties. In this study, we assessed the clinical and radiographic outcomes of patients undergoing primary cementless ceramic-on-ceramic THA at a minimum follow-up of 20 years. METHODS: A series of 301 consecutive primary THAs in 283 patients were assessed. Clinically, patients were assessed with the modified Harris Hip Score (HHS) and pain questionnaires. Anteroposterior radiographs of the pelvis and lateral radiographs of the hip were used to radiologically assess the implant. Patients were classified as lost to follow-up if they could not be contacted on multiple occasions or did not wish to participate further in this study. RESULTS: At twenty years after operation, 60 patients had died of a cause unrelated to surgery, 16 had experienced complications requiring reoperation, and 100 hips had both clinical assessments and radiographs at a minimum of 20 years of follow-up. The average HHS improved from 56.1 (range: 17-89) before THA to 92.5 (range: 63-100) at the latest follow-up. The classification of the HHS was good or excellent in 96.4% of patients. Only 1.8% of patients still had moderate residual pain at the thigh or groin. Radiographically, all patients demonstrated bony ingrowth but no clinical symptoms of loosening. The overall survival rate of the implants was 94.2% at 20 years with revision for any reason as the end point. CONCLUSION: Long-Term follow-up in our series showed excellent implant survival, excellent functional outcomes, and minimal late complications. There was no significant radiographic evidence of failure at a minimum of 20 years after THA. LEVEL OF EVIDENCE: Therapeutic Level IV.

Increase in Benign Squeaking Rate at Five-Year Follow-Up: Results of a Large Diameter Ceramic-on-Ceramic Bearing in Total Hip Arthroplasty.

BACKGROUND: Squeaking is an on-going complication with a variable incidence of 0.5%-20.7%. The mechanism of squeaking has not been understood completely and is most likely multifactorial in nature. Previously, we have reported on a squeaking rate of 7.3% at 2 years. Our current results show a substantial increase in the squeaking incidence from 7.3% to 17.4% with the DeltaMotion articulation at the 5-year follow-up. METHODS: Two hundred six total hip arthroplasties with a large ceramic-on-ceramic bearing were performed on 195 patients by 2 senior authors. The minimum duration of follow-up was 5 years (range 5-6.2). RESULTS: The mean Harris Hip Score remained stable at 91.7 at 5 years compared to 92 after 2 years. However, we observed an increase in the squeaking rate from 7.3% after 2 years to 17.4% after 5 years. As in previous studies, we did not find significant differences between the silent and squeaking group in relation to age, height, weight, and femoral head diameter. In contrast, others reported no significant differences regarding range of motion and gender between the silent and the squeaking hip group at 2 years of follow-up, whereas at 5 years, the squeaking group showed a significantly higher combined range of motion and a higher relative risk of squeaking in women compared to the silent group. CONCLUSION: While large diameter ceramic bearings may produce squeaking, especially in female patients, our mid-term clinical results of a large ceramic-on-ceramic bearing in total hip arthroplasty are encouraging. Nevertheless, long-term follow-up is recommended.

Squeaking in large diameter ceramic-on-ceramic bearings in total hip arthroplasty.

We analyzed the results of 206 consecutive total hip arthroplasties performed using large diameter ceramic-on-ceramic bearings. At an average follow-up of 28months, the mean Harris Hip Score improved from 54 to 92. Fifteen (7.3%) hips were noted to squeak. There was no significant difference between silent and squeaking hips with regards to age, weight, height, BMI, range of movement, femoral head diameter, leg length, and offset or center of rotation. No correlation was present between incidence of squeaking and increasing cup inclination and anteversion. 5.2% of cups orientated within Lewinnek's safe zone squeaked. No hips required revision for squeaking. While large diameter ceramic bearings may produce squeaking, our early results of surgery using large head ceramic bearings are encouraging. However, long-term follow-up is required.

The effect of obesity on the clinical, functional and radiological outcome of cementless total hip replacement: a case-matched study with a minimum 10-year follow-up.

1420 primary cementless THRs with a minimum follow-up of 10-years were stratified according to BMI: non-obese (BMI<30kg/m(2)) and obese (BMI≥30kg/m(2)). Median age at surgery was younger in obese patients (P<0.001). We case-matched 82 THRs in obese patients with 162 THRs in non-obese patients. No difference between groups was found in improvement in HHS (P=0.668), satisfaction with surgery (P=0.644), range of movement, prosthesis orientation, or radiological loosening. The obese cohort was further separated into those with a BMI below and above 35. No difference was found between groups in improvement in HHS, satisfaction with surgery, component orientation, or radiological loosening. There was no difference in the incidence of post-operative complications between obese and non-obese patients. After 10-years, the results of THR are not compromised by obesity.

Factors affecting squeaking in metal on metal hip resurfacings.

We reviewed 380 hip resurfacings cases between December 1999 and Dec 2012. 11 cases (2.89%) squeaked postoperatively. Mean follow-up was 88.6 months (19-130 months). Mean time to squeak was 11.3 months (3-22 months). Ten (91%) cases were male and nine (81%) cases had a Birmingham hip resurfacing. Cases were matched for age, gender, BMI and implant to three controls. Radiographs were analysed using EBRA (Einzel-Bild-Roentgen-Analysis, University of Innsbruck, Austria) software to evaluate cup orientation. There was no significant difference between the mean inclination angle of the cups (p = 0.26) or the mean anteversion angle (p = 0.29). There was no difference in serum cobalt (p = 0.20) or serum chromium (p = 0.45) levels at latest follow-up. Three of the 11 (27.3%) cases had revision surgery at a mean follow-up of 101 months (72-117 months). Squeaking was not influenced by patient demographic parameters and resolved in all cases that did not undergo revision surgery. Males with a resurfacing head size <50 mm had significantly increased odds of squeaking when compared to controls (odds ratio = 26.6; 95% CI = 1.2-573.3; p<0.05). Based on our findings, we do not recommend that squeaking on its own should be an indication for revision of hip resurfacing components.

Fretting and corrosion in modular-neck total hip arthroplasty femoral stems.

BACKGROUND: During total hip arthroplasty, use of a modular femoral neck on a stemmed implant allows optimization of neck anteversion, length, and offset, resulting in more accurate balance. We performed a retrospective analysis of a consecutive cohort of patients who had undergone total hip arthroplasty with a modular-neck hip system with ceramic-on-ceramic bearings. METHODS: We reviewed the results in fifteen patients who had received an ABG II dual modular hip system (Stryker Orthopaedics, Mahwah, New Jersey) from May 2007 to August 2008. Anteroposterior radiographs of the pelvis were reviewed and scored with regard to medial calcar erosion. Magnetic resonance imaging (MRI) was performed to assess for adverse local tissue reaction around the hip joint. Calcar resorption was correlated with subsequent MRI findings. Retrieval analysis was performed on the implants removed at revision. RESULTS: The mean duration of follow-up for all patients was 42.3 months (range, thirty-three to sixty months). Cobalt-ion levels were elevated in all patients; chromium levels were within the normal range. Medial femoral calcar erosion was noted in seven of the fifteen cases. All patients with grade-2 or 3 calcar erosion on radiographs had positive MRI findings consistent with adverse local tissue reaction. At the time of writing, seven patients had undergone revision arthroplasty. Intraoperatively, tissue staining with tissue and bone necrosis and pseudotumor formation were observed in all revision cases. Histological analysis confirmed the presence of metal-on-metal synovitis, with changes similar to those seen with metal-on-metal bearings. CONCLUSIONS: The ABG II dual modular hip system is associated with a high rate of early failure secondary to fretting and corrosion at the femoral neck-stem taper. The component has subsequently been recalled and is no longer in use. Surgeons using modular hip systems with a titanium stem and cobalt-chromium neck should be vigilant about annual follow-up with radiographs, and use of MRIs as indicated.

Human polyethylene granuloma tissues inhibit bone healing in a novel xenograft animal model.

During revision of a conventional polyethylene joint replacement, surgeons usually remove the source of osteolysis (polyethylene) but cannot always remove all of the polyethylene granuloma tissues. We developed a human/rat xenograft model to investigate the effects of polyethylene granuloma tissues on bone healing. Human osteoarthritic and periprosthetic tissues collected during primary and revision hip arthroplasty surgeries were transplanted into the distal femora of athymic nude rats. After 3 weeks in vivo, there was a significant difference in the bone volume fraction (Vf ) between empty, primary, and revision defects (p = 0.02), with a lower Vf in defects with revision granuloma tissues compared to defects with primary osteoarthritic tissues. Polyethylene granuloma tissues in trabecular bone defects inhibited bone healing. Therefore, debridement around a metal-on-polyethylene hip replacement may shorten the time it takes to achieve secondary stability around a revision hip replacement.

Cementless hip arthroplasty in Paget's disease at long-term follow-up (average of 12.3 years).

We present a long-term follow-up report of 33 cementless total hip arthroplasties in 27 patients who have an established diagnosis of Paget's disease. The medium term results of this series were reported in 2007 (Lusty et al. Journal of Arthroplasty. 2007;22:692). Fourteen cases were available for follow-up at an average of 12.3 years (range 10-17). Harris Hip scores improved from 56/100 preoperatively (16-98/100) to 83/100 post operatively (72-90/100). All surviving components were radiographically ingrown. Based on these findings, cementless total hip arthroplasty has a good long-term outcome in Paget's disease.

Squeaking: Current knowledge and how to avoid it.

This review aims to update the reader with current thinking and research related to the well documented phenomenon of squeaking hip arthroplasties. The etiology of squeaking is multifactorial and still not well understood. We aim to share our own experience and views on the combination of factors we believe increases the likelihood of squeaking, along with mechanisms by which the sound may be generated. Recent published findings from other groups are summarized along with an appropriate management algorithm we recommend for this cohort of patients.

Limited slot femorotomy for removal of proximally coated cementless stems. A 10-year follow-up of an unreported surgical technique.

We present a technique of single posterior longitudinal slot femorotomy. This technique allows the expansion of the metaphyseal-diaphyseal region of the proximal femur facilitating extraction of proximally coated uncemented femoral components while leaving the metaphysis and diaphysis intact. Since 1996 we have performed this technique in 18 revision total hip arthroplasties in 15 patients who had x-ray appearance of bony in-growth/on-growth and where found to have solidly ingrown stems at revision surgery. All were revised to a metaphyseally fitting uncemented stem. At mean follow-up of 122.4 months, there were significant improvements in both pain and function. All revised stems achieved stable boney fixation. There were no complications due to this technique. No patient developed a limp or thigh pain postoperatively. There have been no re-revisions of the stem. With appropriate patient selection, this is a simple, reliable, and extensile technique is useful to assist in the extraction of uncemented proximally coated femoral components whether hydroxyapatite-coated or not.

Periprosthetic tissues from third generation alumina-on-alumina total hip arthroplasties.

The histological features of periprosthetic tissues are related to the bioreactivity of particles generated by the prosthesis. This study analyzed synovial-like pseudocapsules collected from 21 patients with alumina ceramic-on-ceramic hip arthroplasties and correlated histological features with wear of the ceramic bearings, duration of implantation and clinical factors such as neck-to-rim impingement. A histopathological classification system was developed for this purpose. The pseudocapsules were viable, with few foreign body type giant cells and occasional lymphocytes. This differs from tissues in polyethylene containing hip arthroplasties which often have extensive foreign body type inflammatory changes or from metal-on-metal hip arthroplasties in which extensive necrosis is common. Soft-tissue inflammation was not associated with failure of the hip arthroplasties, and may be clinically insignificant in alumina-on-alumina total hip arthroplasties.

Mid-term results of third-generation alumina-on-alumina ceramic bearings in cementless total hip arthroplasty: a ten-year minimum follow-up.

BACKGROUND: Alumina ceramic-on-ceramic bearings have gained popularity in hip arthroplasty because of their properties of low wear and chemical inertness. In a previous study, we reported the excellent clinical results in a series of cementless ceramic-on-ceramic primary total hip arthroplasties at a minimum of five years of follow-up. The purpose of the present study was to determine the results in the same patient cohort at a minimum of ten years of follow-up. METHODS: A series of 301 consecutive primary cementless total hip arthroplasties was assessed clinically and radiographically. Clinical information was available for 244 hips in 227 surviving patients at a minimum of ten years of follow-up, and radiographic information was available for 184 hips in 172 patients. RESULTS: Twenty-six (9.2%) of the patients had died of an unrelated cause and eight (2.7%) had undergone revision arthroplasty by the time of the latest follow-up. The average Harris hip score was 94 points, with 95% (232) of the patients having an excellent or good result and <4% (nine) having moderate residual pain. All radiographic assessments showed evidence of stable osseous ingrowth. Nine revisions had been performed, including four femoral component revisions due to periprosthetic fracture, one femoral revision due to aseptic loosening, one femoral revision secondary to a femoral shortening osteotomy for nerve palsy, two acetabular cup revisions due to psoas tendinitis, and a repeat revision in one of the patients with psoas tendinitis due to acetabular osteolysis. The overall survival rate of the implants was 98% (95% confidence interval, 94.2% to 99.6%) at ten years with revision for any reason as the end point. CONCLUSIONS: The patients in our series had a good implant survival rate, good function, a low implant wear rate as reported in the previous study, and no further radiographic evidence of failure at ten years after cementless primary total hip arthroplasty with alumina ceramic-on-ceramic bearings.

Tibial fixation without screws in cementless knee arthroplasty.

This study reexamines the clinical and radiologic results of the first 216 cases of a cementless fixed-bearing tibial tray without screw holes in 191 patients at 7.6-year follow-up (range, 5-10 years). Mean Hospital for Special Surgery scores improved from 54/100 preoperatively to 84/100 postoperatively. Four tibial baseplates were revised. Five polyethylene inserts were revised. The overall reoperation rate was 12%. Four percent of tibial baseplates had incomplete nonprogressive radiolucent lines involving 1 or 2 of 10 defined zones. Overall tibial osteolysis rate was 4.1%. All tibial components were stable by radiographic technique. We conclude that this tibial tray provides reliable stability without the use of screws at medium-term follow-up. The polyethylene failure rate is a concern.

Long term results of cementless total hip replacement for reversal of hip ankylosis.

Fifteen patients (16 hips) with an ankylosed hip joint for a mean of 36 years (3.5 to 65), had their hips converted to a cementless Total Hip Replacement (THR). They were followed-up for a median of 10.75 years (5.0 to 19) with none lost to follow-up. All patients showed improved mobility and function post-operatively. The Harris Hip Score improved from 70 (SEM 3.4) to 83 post-operatively (SEM 4.4), which was statistically significant (p < 0.05). There was one acetabular cup revision at 5 years post implantation for aseptic loosening. All other femoral and acetabular components remained clinically and radiographically well fixed. We conclude that a previously ankylosed hip can be effectively converted to a cementless total hip replacement with good long term results.

Osteolysis with a cementless second generation metal-on-metal cup in total hip replacement.

This study examined the long-term results of a metal-on-metal total hip replacement with a Metasul-lined cup. Twenty-nine total hip arthroplasties were performed in 27 young patients (mean age 49 years). Twenty-two patients (23 hips) were available for clinical and radiographic analysis after a mean duration of 99 months. Mean preoperative Harris hip score of 60 improved to 93 at most recent follow-up. One patient required revision of his cup for periacetabular osteolysis. Radiographic analysis showed osteolysis in another four hips. The high rate of osteolysis found in this series has not previously been reported with this type of implant. The length of follow-up in this series is greater than other reports in the literature and may explain this difference.

Osteolysis in third-generation alumina ceramic-on-ceramic hip bearings with severe impingement and titanium metallosis.

The most common cause of long-term failure of total hip arthroplasty is osteolysis and aseptic loosening secondary to wear debris. Combinations of hard materials such as ceramic-on-ceramic generate smaller volumes of particulate wear debris than traditional combinations such as metal-on-polyethylene. We describe 2 cases where osteolysis arose in hips with third-generation alumina ceramic-on-ceramic couplings. Periarticular tissue in both cases contained titanium wear debris due to impingement of the neck of the titanium femoral component against the rim of the titanium shell and ceramic debris from edge loading wear (stripe wear) of the ceramic. It is not clear whether the titanium debris, the ceramic debris, or both caused the osteolysis. These cases illustrate that the risk of osteolysis persists, even with third-generation alumina ceramics.

Cementless hip arthroplasty in Paget's disease at medium-term follow-up (average of 6.7 years).

We performed 33 cementless total hip arthroplasties for arthritis in 27 patients with an established diagnosis of Paget's disease on the acetabular or femoral side of the hip. There were 3 revisions. One stem for aseptic loosening at 55 months, and 2 stems after periprosthetic fractures at 9 and 70 months. Twenty-three cases were available for follow-up at an average of 6.7 years (range, 2-14 years). Harris hip score improved from 56/100 preoperatively (16-98/100) to 90/100 postoperatively (78-100/100). All surviving components were radiographically bone ingrown. Based on our findings, it appears that a cementless total hip arthroplasty can have a good outcome in Paget's disease.

Squeaking in ceramic-on-ceramic hips: the importance of acetabular component orientation.

Audible squeaking in total hip replacements with ceramic-on-ceramic bearings is a rare problem. Acetabular component orientation was compared for 17 squeaking hips and 17 matched controls. Ninety-four percent of control hips were in a range of 25 degrees +/- 10 degrees anteversion and 45 degrees +/- 10 degrees inclination, but only 35% of squeaking hips were in this range (P = .0003). Eight hips squeak with bending. Four hips squeak with walking, and 5 hips squeak after prolonged periods of walking. Hips that squeaked with walking had acetabular components that were more anteverted (40 degrees ) than hips that squeaked with bending (19 degrees ) (P = .001) or prolonged walking (18 degrees ) (P = .020). The hips started squeaking after an average of 14 months. Patients with squeaking hips were younger, heavier, and taller than patients with silent hips.

Iliopsoas tendonitis a complication after total hip arthroplasty.

The causes of pain after total hip arthroplasty are multiple. We present a series of 15 patients (16 cases) who presented with pain related to the iliopsoas tendon. All patients had previously undergone cementless hip arthroplasty and presented with similar symptoms and clinical signs. Surgery was carried out after failure of conservative measures. Release of the iliopsoas tendon from the lesser trochanter gave good symptomatic relief in all except one patient who required reposition of acetabular prosthesis, with the average Harris Hip Score improving from 58 (range, 44-70) to 91 (range, 78-95) postoperatively. This relatively uncommon condition should be considered in the differential diagnosis of all patients who present with groin pain after total hip arthroplasty. Surgical release of the iliopsoas tendon can give excellent results in these patients.

Clinical and radiographic assessment of a modular cementless ingrowth femoral stem system for revision hip arthroplasty.

This article presents 6-year mean (2-12-year) clinical and radiographic follow-up of 62 proximally porous-coated modular S-ROM femoral revisions. These patients come from 106 consecutive cases in 97 patients performed by one surgeon between 1987 and 1992 without structural allograft (femoral bone loss was Paprosky types 1-3B). In the 99 cases with known outcome, there were 7 postoperative complications: 2 dislocations (2%), 2 deep infections (2%), 2 periprosthetic femoral fractures (2%), and 1 transient sciatic nerve palsy (1%). There was only 1 revision of the index surgery for a problem related to the stem (dislocation). Of the 62 stems, 59 (95%) with complete follow-up were ingrown, 2 (3%) were loose, and 1 had stable fibrous fixation. This represents a mechanical failure rate of 5%. Stems greater than 16 mm in diameter were more likely to show stress shielding (P = .009) and not to be ingrown (P = .0006).