J. Mokka

Adverse reaction to metal debris after ReCap-M2A-Magnum large-diameter-head metal-on-metal total hip arthroplasty

Background and purpose The clinical findings of adverse reaction to metal debris (ARMD) following large-diameter-head metal-on-metal total hip arthroplasty (LDH MoM THA) may include periarticular fluid collections, soft tissue masses, and gluteal muscle necrosis. The ReCap-M2a-Magnum LDH MoM THA was the most commonly used hip device at our institution from 2005 to 2012. We assessed the prevalence of and risk factors for ARMD with this device. Methods 74 patients (80 hips) had a ReCap-M2a-Magnum LDH MoM THA during the period August 2005 to December 2006. These patients were studied with hip MRI, serum chromium and cobalt ion measurements, the Oxford hip score questionnaire, and by clinical examination. The prevalence of ARMD was recorded and risk factors for ARMD were assessed using logistic regression models. The mean follow-up time was 6.0 (5.5–6.7) years. Results A revision operation due to ARMD was needed by 3 of 74 patients (3 of 80 hips). 8 additional patients (8 hips) had definite ARMD, but revision was not performed. 29 patients (32 hips) were considered to have a probable or possible ARMD. Altogether, 43 of 80 hips had a definite, probable, or possible ARMD and 34 patients (37 hips) were considered not to have ARMD. In 46 of 78 hips, MRI revealed a soft tissue mass or a collection of fluid (of any size). The symptoms clicking in the hip, local hip swelling, and a feeling of subluxation were associated with ARMD. Interpretation ARMD is common after ReCap-M2a-Magnum total hip arthroplasty, and we discourage the use of this device. Asymptomatic patients with a small fluid collection on MRI may not need instant revision surgery but must be followed up closely.

Up to 10 Years Follow up of the Use of 71 Cortical Allografts (Strut-Grafts) for the Treatment of Periprosthetic Fractures

Backround and Aims: Periprosthetic fractures are often located in areas of poor bone quality. There are multiple strategies to manage these fractures. Stable fixation in areas of low bone quality may require the use of cortical bone strut allografts. Material and Methods: Cortical allograft struts were used in the treatment of 71 patients with periprosthetic fractures between a 10 year period from 1/1999 untill 12/2008. 18 patients had a periprosthetic fracture around the knee implant, 52 around the hip implant and 1 in between the hip and knee prosthesis. The average follow-up time was 943 days ranging from 90 days to 3428 days. Results and Conclusions: The overall union rate was 91%. 20 patients died during the follow-up, 6 of them during the first six month after operation. 8 patients (12%) had an diagnosed infection during the follow-up time. The specific strategy chosen to periprostehetic fracture treatment should depend on the quality of the remaining bone stock, type of the implant, location and classification of the fracture and on patients related factors, such age age and comorbidities. Use of cortical bone struts is a good option in fractures associated with poor bone quality. Use of allograft strut combined with a nonlocking plate, which offers the highest stiffness known, may provide superior biomechanical stability compared with other methods in some situations.

Early Results of Large Head Metal-on-Metal Hip Arthroplasties

Background and Aims Total hip arthroplasty significantly improves patients life quality. However, total joint replacement is associated with possible complications, such as dislocations, infections, fractures and periprosthetic osteolysis. The goal of this study was to evaluate a large head metal-on-metal total hip arthroplasties and analyse short term complications related to them. Material and Methods Between 9/2005 and 6/2009, a total of 691 hip replacements were performed on 635 patients with the use of Magnum M2 large head cementless metal-on-metal prosthesis in Turku University Hospital. All patients had a scheduled follow-up at two to three months, and at one year. The results were evaluated using X-rays, Harris Hip Score (HHS), and evaluating post-operative complications and reasons for re-operations. Results During our follow-up the HHS median raised from its preoperative value of 59.8 to 86.4 two to three months after the operation, and to 93.9 one year after the operation. As a complication we had five infections requiring single open debridement (early infection) or a two stage revision. Seven patients had a periprosthetic femoral fracture that was operated and 11 patients were reoperated because of acetabular component malposition, fracture or early loosening. We did not observe any dislocations, n. ischiadicus damages, squeeking or complications related to high metal ion release (ALVAL-reactions (Aseptic Lymphocyte-dominated Vasculitis-Associated Lesion) or pseudotumours). Conclusions The metal-on-metal bearing pair allows large femoral head size, which decreases the risk for dislocation. It may also decrease the risk for osteolysis and aseptic loosening in a long run. Early complication rate related to the bearing surface is minimal. Metal-on-metal prosthesis is a good choice for young and active patients with good bone quality.

Is it feasible to merge data from national shoulder registries? A new collaboration within the Nordic Arthroplasty Register Association

BACKGROUND The Nordic Arthroplasty Register Association was initiated in 2007, and several papers about hip and knee arthroplasty have been published. Inspired by this, we aimed to examine the feasibility of merging data from the Nordic national shoulder arthroplasty registries by defining a common minimal data set. METHODS A group of surgeons met in 2014 to discuss the feasibility of merging data from the national shoulder registries in Denmark, Norway, and Sweden. Differences in organization, definitions, variables, and outcome measures were discussed. A common minimal data set was defined as a set of variables containing only data that all registries could deliver and where consensus according to definition of the variables could be made. RESULTS We agreed on a data set containing patient-related data (age, gender, and diagnosis), operative data (date, arthroplasty type and brand), and data in case of revision (date, reason for revision, and new arthroplasty brand). From 2004 to 2013, there were 19,857 primary arthroplasties reported. The most common indications were osteoarthritis (35%) and acute fracture (34%). The number of arthroplasties and especially the number of arthroplasties for osteoarthritis have increased in the study period. The most common arthroplasty type was total shoulder arthroplasty (34%) for osteoarthritis and stemmed hemiarthroplasty (90%) for acute fractures. CONCLUSION We were able to merge data from the Nordic national registries into 1 common data set; however, the set of details was reduced. We found considerable differences between the 3 countries regarding incidence of shoulder arthroplasty, age, diagnoses, and choice of arthroplasty type and brand.

Cementless Total Hip Arthroplasty with Large Diameter Metal-on-Metal Heads: Short-Term Survivorship of 8059 Hips from the Finnish Arthroplasty Register

Background and Aims: Population-based register data from the National Joint Register of Australia and England and Wales have revealed that the mid-term outcome of cementless large diameter head metal-on-metal total hip arthroplasty is inferior to that of conventional cemented metal-on-polyethylene total hip arthroplasty. The aim of this study was to compare the results of cementless large diameter head metal-on-metal total hip arthroplasty with conventional cemented arthroplasty in Finland. The second aim of this study was to compare the cementless large diameter head metal-on-metal models with each other. Material and Methods: Based on the data extracted from the Finnish Arthroplasty Register, the risk of revision of 8059 cementless large diameter head metal-on-metal total hip arthroplasties performed during 2002–2009 was analyzed using Cox regression model. The revision risk of these hips was compared to that of 16,978 cemented metal-on-polyethylene total hip arthroplasties performed during the same time period. Results: In the Cox regression analysis, there was no difference in revision risks between cementless large diameter head metal-on-metal total hip arthroplasty and cemented metal-on-polyethylene total hip arthroplasty (relative risk = 0.90, confidence interval = 0.74–1.10, p = 0.3). However, in female patients aged 55 years or above, cementless large diameter head metal-on-metal total hip replacements showed a significantly increased risk of revision as compared to cemented total hip replacements (relative risk = 1.33, confidence interval = 1.04–1.70). Compared to the reference implant in this study (cementless Synergy stem combined with Birmingham Hip Resurfacing [BHR] cup), the CementLess Spotorno (CLS) stem combined with Durom cup had a 2.9-fold (95% confidence interval = 1.17–6.90) increased risk of revision. Conclusions: We found that cementless large diameter head metal-on-metal total hip arthroplasty had short-term survivorship compared with cemented total hip arthroplasty at a nation-wide level. However, in female patients aged 55 years or above, cementless large diameter head metal-on-metal total hip arthroplasty showed inferior results. Furthermore, implant design had an influence on revision rates. Longer follow-up time is needed to assess the success of large diameter head metal-on-metal total hip arthroplasty.

Adverse reaction to metal debris after Birmingham hip resurfacing arthroplasty

Background and purpose — Concern has emerged about local soft-tissue reactions after hip resurfacing arthroplasty (HRA). The Birmingham Hip Resurfacing (BHR) was the most commonly used HRA device at our institution. We assessed the prevalence and risk factors for adverse reaction to metal debris (ARMD) with this device. Patients and methods — From 2003 to 2011, BHR was the most commonly used HRA device at our institution, with 249 implantations. We included 32 patients (24 of them men) who were operated with a BHR HRA during the period April 2004 to March 2007 (42 hips; 31 in men). The mean age of the patients was 59 (26–77) years. These patients underwent magnetic resonance imaging (MRI), serum metal ion measurements, the Oxford hip score questionnaire, and physical examination. The prevalence of ARMD was recorded, and risk factors for ARMD were assessed using logistic regression models. The mean follow-up time was 6.7 (2.4–8.8) years. Results — 6 patients had a definite ARMD (involving 9 of the 42 hips). 8 other patients (8 hips) had a probable ARMD. Thus, there was definite or probable ARMD in 17 of the 42 hips. 4 of 42 hips were revised for ARMD. Gender, bilateral metal-on-metal hip replacement and head size were not factors associated with ARMD. Interpretation — We found that HRA with the Birmingham Hip Resurfacing may be more dangerous than previously believed. We advise systematic follow-up of these patients using metal ion levels, MRI/ultrasound, and patient-reported outcome measures.

Acetabular reconstruction with impaction bone grafting and cemented polyethylene socket in total hip revision arthroplasty.

Background and aims: Bone deficiency in revision total hip arthroplasty is a challenge to the surgeon. One option for restoration of the bone stock is impaction bone grafting and use of a cemented socket. The aim of this study was to evaluate the mid-term clinical outcome of impaction bone grafting and cemented socket revisions. Material and methods: A total of 59 patients (60 hips) underwent revision arthroplasty with impaction bone grafting and application of a cemented socket on the acetabular side in the Turku University Hospital from 1999 to 2004. The study end-point was re-revision for any reason. The cumulative percentages for survival were followed and estimated with Kaplan–Meier curves. Associations between occurrence of re-revision and potential risk factors were analyzed with logistic regression. Results were quantified by odd ratios and 95% confidence intervals. The mean age of the patients was 69 years (33% male). A total of 3% of the patients had a class I Paprosky acetabular defect, 38% had class II, and 55% had class III. Results: The overall survival rate was 73%. The mean follow-up time was 7 years. The most common reason for re-revision was aseptic loosening of the acetabular component (13 patients, 81% of re-revisions). Cox’s regression analysis did not identify any risk factors for re-revision. Conclusion: Our results were inferior compared to some previous studies. Impaction bone grafting of acetabular defects in revision total hip arthroplasty may not always provide a reliable bone stock in long-term.

Experience of structural onlay allografts for the treatment of bone deficiency in revision total hip arthroplasty

Background and Aims: Loss of femoral bone stock in elective revision total hip arthroplasty poses unique and substantial challenges. Structural onlay allografts may provide mechanical stability for the cementless revision prosthesis and increase bone stock. Material and methods: At least one cortical onlay allograft was used in 40 elective total hip arthroplasty revisions (40 patients) to reconstruct femoral bone defects. The operations were performed between January 1999 and August 2010 in the Turku University Hospital, Finland. The mean follow-up time was 52 months (range: 12–125 months). Results: The allografts were incorporated into the bone tissue in 37 of 40 (92.5%) patients. Cementless revision stems healed in 36 of 40 (90.0%) patients, but these patients were not exactly the same patients whose allografts were successfully incorporated. One or more surgical complications were experienced by 14 of 40 (35.0%) patients during follow-up. In all, 4 of 40 (10.0%) patients (all women) had hip infections during follow-up. Of the 7 patients with rheumatoid arthritis, 4 (57.1%) had at least one complication. Conclusions: The use of the cortical onlay allografts provides a feasible option for restoring the integrity of the proximal femur in revision total hip arthroplasty, but the complication rate is high, particularly in female patients with rheumatoid arthritis.

Risk and risk factors for revision after primary reverse shoulder arthroplasty for cuff tear arthropathy and osteoarthritis: a Nordic Arthroplasty Register Association study

BACKGROUND Reverse shoulder arthroplasty (RSA) has gained increasing popularity in the treatment of rotator cuff tear arthropathy (CTA). The purpose of this study was to evaluate the survival of RSA and the risk factors for revision following RSA. METHODS RSA patients with CTA or osteoarthritis were identified from the Nordic Arthroplasty Register Association registry data (2004-2013). Kaplan-Meier survival analysis was used to calculate survival probabilities. Cox multiple regression analysis was used to calculate revision rates adjusted for sex, arthroplasty brand, age (<70 years), and year of surgery. RESULTS The study included 1904 patients with RSA (1904 RSAs) (69% women; mean age, 74 years; age range, 35-97 years). Revision was performed in 95 patients (5%), with a 10-year cumulative revision rate of 0.91. The most common reason for revision was infection (n = 42), followed by loosening (n = 16) and instability (n = 12). Most revisions occurred less than 6 months after the primary operation. Men had a significantly increased risk of revision compared with women (risk ratio, 3.8; 95% confidence interval, 2.4-6.1). The most common implants were the Delta Xtend (n = 1366) and Delta Mark III (n = 246). The risk of revision of the Delta Mark III was 2.1 (95% confidence interval, 1.1-4.3) compared with the Delta Xtend. Age and year of surgery were not statistically significantly associated with risk of revision. CONCLUSION The overall midterm risk of revision after RSA for CTA was low (5%). The most common reason for early revision was infection. Male sex was associated with a significantly increased risk of revision.

Reverse Shoulder Arthroplasty in the Treatment of End-Stage Rheumatoid Arthritis of the Shoulder

Background and purpose: Natural history of the rheumatoid shoulder will lead to upward migration, medialization and flattening of the humeral head causing loss of motion. Mechanically reversed shoulder Arthroplasty can prevent upward migration of humerus and restore shoulder motion. We evaluated pain relief and shoulder function after reversed Arthroplasty in RA; determined the rate of scapular notching; and determined the complication rate Patients and Methods: We identified 76 reverse shoulder artroplasties with RA from consecutive RA patients having the surgery from 2007 to 2013. Mean follow-up was 27 months (range 12-84) and mean age at operation was 70 years (range49-90) all patients were evaluated preoperatively and at follow-up study by an independent observer (our physiotherapists). Level of pain, range of motion were recorded and radiographes taken and analyzed by an orthopaedic surgeon. Results: Visual Analog Scale score for pain at motion decreased from 7.0 to 1.0 and score for pain at rest from 4.0 to 1.0. Some kind of complication developed to 11 (14%) patients. Notching occurred in 32% of shoulders but no loosening was seen. Interpretation: Reverse shoulder Arthroplasty improved shoulder functions with a low incidence of complications in Rheumatoid Arthritis. We believe it should be used more often in patients with Rheumatoid Arthritis because the results with familiar total shoulders are disappointing in rheumatoid patients.