Incidence and risk factors for bilateral proximal femoral fractures.

BACKGROUND: Proximal femoral fractures (PFFs) are a public health issue due to their high frequency. The frequency of a second PFF on the other side is estimated at 10%. This estimation is controversial, however, and the risk factors have not been evaluated in a large population of French patients. The objective of this retrospective case-control study was to determine: (1) the incidence of second PFFs and (2) their risk factors. HYPOTHESIS: The incidence of second PFFs is >2% after 1 year and >5% after 3 years. MATERIAL AND METHODS: We conducted a case-control study in a population of consecutive patients managed surgically for PPF at the Lyon Sud Hospital between 2013 and 2014. We analysed the following clinical factors: age, sex, body mass index (BMI), institutionalisation, the Parker score, the American Society of Anesthesiologists score (ASA), comorbidities, and the use of psychoactive drugs. RESULTS: We included 474 PFFs (trochanter, n=240 and neck, n=234) of which 36 were bilateral. The contralateral fracture occurred within 1 year of the first fracture in 6/474 (1.3%) cases and within 3 years in all 36 cases (7.6%). The case-control study comprised 49 cases with bilateral PFF and 161 controls with no second hip fracture within 3 years. Risk factors for a second hip fracture were age older than 90 years (odds ratio [OR]=5.44; 95% confidence interval [95%CI], 112-2642 (p=0.002)) and a history of heart disease (OR, 2.18; 95%CI, 1.06-4.47 [p=0.03]). A Parker score≥6 was protective (OR, 0.84; 95%CI, 0.71-0.99 [p=0.03]). Mortality after 3 years was 42% (201/474), and 13% (63/474) of patients were lost to follow-up. DISCUSSION: Age older than 90 years, a Parker score below 6, and a history of heart disease are risk factors for a second PFF within 3 years after the first PFF. LEVEL OF EVIDENCE: III; case-control study.

Metasul vs Cerasul bearings: a prospective, randomized study at a mean eighteen years.

BACKGROUND: The aims of our study were to compare the clinical, radiographic outcomes and survivals between second-generation metal-on-metal (Metasul) and ceramic-on-ceramic (Cerasul) bearings at a very long-term follow-up. METHODS: A prospective, randomized study was originally performed on a consecutive series of 250 cementless, 28-mm head and primary total hip arthroplasties between 1999 and 2002. For each bearing (Metasul or Cerasul), 125 THAs were initially included. All cases were evaluated both clinically and radiographically, and survival was assessed, considering revisions for aseptic loosening or for any reason as the end points for failure. RESULTS: At a mean 18-year follow-up, clinical and radiographic outcomes were similar. Harris Hip Score increased 30% in the Metasul group and 32% in the Cerasul group (p = 0.6). Survival free of aseptic loosening was higher for Cerasul (100%), than for Metasul (94% [CI 88-99.9]) (p = 0.04). Survival free of any revision was 91% ([CI 84-98%]) for Cerasul and 91% ([CI 84-98%]) for Metasul. Fractures of Cerasul insert occurred in four cases (3%) at a mean 12.5 ± 3.3 years (range, 6 to 17 years). CONCLUSION: At 18 years, Cerasul demonstrated higher survivorship than Metasul considering aseptic loosening as an end point. However, Cerasul liners had high rate of fracture because of its sandwich design (thin ceramic liner into polyethylene). These implants are no more available on the market.

Atypical biceps-related complication of proximal humerus fracture leading to internal shoulder impingement due to tendon stump dislocation.

Non-displaced proximal humerus fractures are usually managed non-operatively despite of minor malalignment. Biceps tendon rupture due to attrition after malunion is rare around the proximal humerus. Rupture of the long head of biceps (LHB) tendon usually occurs inside the joint close to the origin at the labrum. Treatment is usually non-operative with good outcomes. We report a rare case of a 48-year-old female patient with persistent locking and internal impingement 8 months after a proximal humerus fracture with anterior angulation leading to extra-articular reversed LHB tendon rupture with intra-articular dislocation of the proximal stump. Interposition of the tendon (3.5 cm) between the glenoid and the humeral head was confirmed on MRI arthrogram. Arthroscopic proximal tenotomy and stump removal resulted in immediate relief with improved function (subjective shoulder value 95%; Constant Score: 96). False interpretation of symptoms as posttraumatic stiffness should be avoided by a thorough examination and complementary MRI arthrogram investigation.

Radiographic and Clinical Comparison of Proximal Interphalangeal Joint Arthrodesis Between a Static and Dynamic Implant.

Hammertoe deformation is a frequent motive for consultation in forefoot surgery, and proximal interphalangeal joint arthrodesis is a classic treatment for fixed deformation, which tends to be achieved more and more thanks to specific implants. This work evaluated and compared clinical improvement, radiologic fusion, and complication rates between dynamic (Difuse®) and static (TinyFix®) implants from Biotech Ortho. A total of 95 patients (110 feet and 166 toes; 97 static and 69 dynamic implants) were included. Mean age was 63.6 (±12.6) years in the dynamic group and 62.3 (±14.01) years in the static group. Epidemiologic and intraoperative radiologic data were collected. Pain, toes deformity, complications, and radiologic findings (bone fusion and osteolysis) were recorded at 4 months postoperatively and at the last follow-up. Mean follow-up was 11.5 (range 4 to 28) months, and the position of the implants was more often satisfying in the dynamic group (p = .01). Fusion rates at 4 months were 67% and 80% in the dynamic and static groups, respectively (p = .05). Radiologic osteolysis occurred more frequently in the dynamic group (p = .05 at 4 months), and pain was still present in 3% in the dynamic group at the last follow-up compared with 7% in the static group. Complication rate was 7% in the dynamic group (implant fractures) and 4% in the static group. Revision was considered more often in the dynamic group (p = .01). The static titanium implant seems superior to the dynamic memory shape implant in Nitinol alloy with regard to fusion (p = .04), complications (p = .03), and revision rates (p = .01). The literature review seems to support the good results of static implants compared with the rest of the available arthrodesis implant solutions.

A comparative study about the incidence of dislocation and peri-prosthetic fracture between dual mobility versus standard cups after primary total hip arthroplasty.

PURPOSE: Dislocation and peri-prosthetic fracture (PPF) are major reasons for revision THA (total hip arthroplasty). The main advantage of dual mobility (DM) cups is to minimize the incidence of dislocation compared to single mobility (SM) cups. We hypothesized that the use of DM would lead to an increased risk of PPF because of its greater stability. In contrast, standard cups would be at higher risk of dislocation. METHODS: A retrospective comparative study was performed in our institution including 126 revision THAs between January 2013 and December 2017. Collected data included gender, age, BMI, Parker score, ASA score, the etiology for primary THA, type of cup (SM or DM), cortical index, Noble index, and the stem fixation. RESULTS: Overall, 53 standard and 73 DM cups were included for study. In the dislocation group, 29 had standard cups (83%) and 6 had DM cups (17%). Dislocation was 12-fold higher in SM cups (p < 0.001). In the PPF group, 24 had standard cups (26%) and 67 had DM cups (74%). PFF was 12-fold higher for DM cups (p < 0.001). A higher Parker score and a higher cortical index had a protective effect on the risk of PPF (OR = 0.76 (p = 0.03), OR = 0.57 (p = 0.048)). CONCLUSION: The use of DM increased hip stability but led to a higher rate of PPF by load transfer on the femur. Further studies with larger cohort and follow-up are needed to confirm these findings and measure the incidence of these complications.

Long-term survivorship of a monoblock long cementless stem in revision total hip arthroplasty.

PURPOSE: The purpose of this study was to assess the clinical outcomes, complications, and survival of a long cementless titanium femoral stem in revision total hip arthroplasty (THA) at a minimum five year follow-up. METHODS: Between 2000 and 2010, 114 patients (116 hips), with a mean age of 68 ± 12 years, underwent revision THA using a KAR® stem (DePuy, Leeds, UK). The main reasons for revision were aseptic loosening (82%), periprosthetic joint infections (PJI) (11%), and periprosthetic fractures (6%). Mean follow-up was ten ± three years (range, 5-16). Harris Hip Score (HHS), Oxford Hip Score (OHS), and Postel-Merle d'Aubigné (PMA) score were recorded. Radiographic analysis assessed stem osseointegration and subsidence. Survival was analyzed using the Kaplan-Meier (KM) method and cumulative incidence function (CIF). RESULTS: Post-operative HHS was 83 ± 15 (range, 35-99) and OHS was 37 ± 8 (range, 8-48). PMA score significantly increased from 12 ± 2 (range, 5-18) pre-operatively to 14.6 ± 2 (range, 9-18) post-operatively (p = 0.0004). The radiographic Engh score was 15 ± 8 (range, 7-22). Stem subsidence was observed in two cases (3%). At ten years, five stems had been revised, three for infections and two for periprosthetic fractures. Using the KM method, ten year survival free of stem revision for aseptic loosening was 100%, free of revision for any reason 95%, and free of any re-operation 81%. CONCLUSIONS: The present study reported satisfactory outcomes and survival of a long tapered unlocked cementless femoral stem in revision THA at a minimum follow-up of five years.

Is dual mobility associated with an increased risk of revision for infection? Matched cohort of 231 cases of dual-mobility cups and 231 fixed cups.

INTRODUCTION: We used a matched cohort of 231 cases of revision of primary dual-mobility cups (DMC) total hip arthroplasty (THA) and 231 cases of fixed cups (FC) THA, to determine whether (i) revision for infection was more frequent when using DMC-THA than FC-THA; (ii) Causes for revision were significantly different. METHODS: The French Society of Orthopaedics and Traumatology carried out a prospective multicentre study from 2010 to 2011. The inclusion criterion was an exhaustive collection of 1st revision THA (at least 1 component revised, re-revision excluded). 2,044 1st revision cases were prospectively collected; 251 (13.5%) were revision of DMC-THA and 1,793 were revision of FC-THA (87.7%). We defined a matching process (1:1) between the 2 cohorts. 231 DMC-THAs were eligible for comparison with 231 FC-THAs. RESULTS: 47 (20.3%) FC-THAs were revised for infection and 54 (23.3%) DMC-THAs. There was no statistical difference (p = 0.43). 41 (17.7%) FC-THAs were revised for dislocation, compared to 11 (4.7%) DMC-THAs (p<0.001). DISCUSSION: The main finding of our study was that DMC was not associated with an increased risk of revision for infection compared to standard THA. THA revision for infection was not correlated to the type of cup used. It is mandatory to report on comparable types of patients when comparing outcomes. For similar patient profiles (i) DMC-THAs were not revised more often for infection than FC-THA (ii) FC-THAs were revised 4 times more for dislocation than DMC-THA.

Teriparatide treatment in an adult patient with hypophosphatasia exposed to bisphosphonate and revealed by bilateral atypical fractures.

Atypical femoral fractures are defined as atraumatic fractures located in the subtrochanteric region or femoral shaft. They have been mainly reported in patients taking bisphosphonates. We report the case of a 67-year-old female with osteoporosis treated by alendronate during ten years. Radiographies showed atypical femoral fractures. Serum levels of total and bone-specific alkaline phosphatase were low. In order to accelerate bone healing, teriparatide was introduced. After one year of teriparatide treatment, pain and functional difficulty have decreased, and alkaline phosphatase levels were normalized. In view of this history of recurrent fractures, of atypical femoral fractures, of early spontaneous loss of teeth, and of low serum total and bone-specific alkaline phosphatase levels, the diagnosis of hypophosphatasia has been considered and confirmed by genetic research. Other conditions than exposure to anti-resorptive therapies may promote atypical femoral fractures, such as in conditions associated with abnormal bone structures, as hypophosphatasia, a rare inherited bone metabolism disorder. A few case reports have reported adult hypophosphatasia treated by teriparatide with a good efficacy on bone pain and consolidation but with mixed results on biological markers. Teriparatide may be therefore a treatment option in adult hypophosphatasia. ALP levels should be carefully checked among osteoporotic patients and specially before introducing a bone resorption inhibitor. Low alkaline phosphatase levels have to be taken into account and an evocative history of hypophosphatasia has to be sought because this condition may expose patients to develop atypical femoral fractures during bisphosphonate treatment.

Dual mobility cups in revision total hip arthroplasty.

AIM: The purpose of our study was to evaluate the dislocation and aseptic loosening rates of a dual mobility construct in revision total hip arthroplasty (THA). METHODS: Three hundred thirty-four revision THAs performed between 2006 and 2011, using a dual mobility cup, were included in this retrospective study. The indications for revision were aseptic loosening (70%), infection (21%) and recurrent instability (9%). The minimum follow-up was five years (mean 7 ± 2 years, maximum 10 years). RESULTS: At the latest follow-up, 11 episodes of dislocation occurred, seven of which were recurrent (1.3% for aseptic loosening, 2.8% for infection and 3.4% for recurrent dislocation). Ten cases of aseptic loosening occurred; in seven of them, a cemented cup into a reinforcement ring had been used (OR = 14, p = 0.0001). CONCLUSION: This study provided evidence of the advantages of dual mobility cups in all revision THA indications.

Causes for revision of dual-mobility and standard primary total hip arthroplasty : Matched case-control study based on a prospective multicenter study of two thousand and forty four implants.

INTRODUCTION: The causes for revision of primary total hip arthroplasty (THA) are various and quite well known. The developing use of dual-mobility THA (DM-THA) seems a relevant option to decrease the risk of instability. Due to lack of long-term follow-up, this innovative retentive concept is suspected to increase the risk of polyethylene (PE) wear. the aim of the study was to analyse the causes for DM-THA revision and assess whether or not its occurrence is different from that of fixed-standard (FS) THA , particularly for aseptic loosening or wear and/or osteolysis. MATERIALS AND METHODS: The SoFCOT group conducted an observational prospective multicentre study from 1 January 2010 to 31 December 2011. Inclusion criteria comprised an exhaustive collection of 2044 first-revision THAs with 251 DM-THAs and 1793 FS-THAs. After excluding complications linked to patient factors (infection and periprosthetic fractures), we performed a matched case-control study (matching ratio 1:1) comparing two groups of 133 THAs. RESULTS: Revisions for aseptic loosening or osteolysis/wear were as frequent in DM-THA (58.7 %) as in FS-THA (57.1 %) (p 0.32); 7.5 % of DM-THA were revised for dislocation versus 19.5 % of FS-THA (p 0.007). DISCUSSION: Revision for osteolysis/wear and aseptic loosening were as frequent in DM-THA as in FS-THA; revision for dislocation was less frequent in DM-THA. This confirms the efficiency of the DM concept regarding the risk of dislocation. Causes for revision were different between groups, and revisions for dislocation were less frequent in DM-THA. Only prospective comparative studies could provide reliable information that may support broader use of the DM concept.

Prospective longitudinal study of one hundred patients with total hip arthroplasty using a second-generation cementless dual-mobility cup.

PURPOSE: The aim of our study was to assess the radio-clinical results, mid-term survivorship and dislocation rate of a new-generation dual-mobility cup. METHODS: The first 100 patients (104 primary total hip arthroplasties) who were implanted with a new-generation cementless dual-mobility cup (Sunfit TH, Serf, Décines) were included in our study, with a minimum follow-up of five years. RESULTS: Average follow-up was six years ± 0.44 (5-7). At last follow-up, the Harris and PMA scores were significantly improved, from 56 to 94 and 13 to 17 respectively (p < 0.001). No radiolucent line could be observed. There were no cases of prosthetic or intraprosthetic dislocation in our series. Survivorship without cup loosening as the endpoint was 100 %. CONCLUSIONS: This study confirmed the interest of dual mobility in preventing prosthetic hip dislocation. Intraprosthetic dislocation is a complication that seems to have been resolved in the mid-term follow-up.

Anatomical study of the medial patello-femoral ligament: landmarks for its surgical reconstruction.

PURPOSE: The aim of this dissection study was to describe the anatomical insertions of the medial patello-femoral ligament (MPFL), and to assess its relationship with surrounding structures to improve its surgical reconstruction. METHODS: Twelve knees (7 cadavers) were included for the study. Measurements and general features of the MPFL were assessed: lengths, widths and insertions. RESULTS: The MPFL was found in all knees, presenting a triangular shape, and extending from the medial part of the patella to its femoral insertion (its length was of 59 ± 6.6 mm), distal to the adductor tubercle. The mean femoral insertion of the MPFL was 7.2 ± 2.7 mm proximal and 7.4 ± 4.0 mm posterior to the medial femoral epicondyle (MFE). It was also at a mean 11 ± 2.8 mm distal and 1.3 ± 2.1 mm posterior to the adductor tubercle, and 22 ± 6.4 mm anterior to the posterior condyle. We did not find any double-bundle organization on the patellar insertion. The width of the MPFL was 8.8 ± 2.9 mm at the femoral insertion, 27 ± 5.9 mm at the patellar insertion, and 12 ± 3.1 mm in the middle of the MPFL. The vastus medialis obliquus was found to be inserted on the superior part of the MPFL. CONCLUSION: The adductor tubercle appeared to be a better landmark than the MFE for the femoral tunnel positioning during surgical reconstructions of the MPFL because it was easier to identify and its relationship with the femoral insertion of the MPFL was constant (10 mm below).

An evaluation of CT-scan to locate the femoral head centre and its implication for hip surgeons.

PURPOSE: The aim of this preliminary study was to determine the accuracy of CT-scan to locate the femoral head centre. METHODS: Eleven dried femurs were included for study. Three techniques were compared to determine femoral head centre (FHC) location: CT-scan, Motion Analysis and Faro-Arm. Markers were stuck on each femur to create a system of coordinates. Femurs lied on their posterior parts (bicondylar plane). Several points around the femoral head were palpated (Motion Analysis and Faro-Arm) or determined (Amira software for CT-scans). By a least-square regression method, the FHC location in 3D was defined for each technique. RESULTS: The results of the FHC location determined by the CT-scan technique were compared with those measured by the faro-arm and the Motion Analysis techniques. The coordinates (X, Y, Z) of the FHC were compared between the three methods, and no statistical difference was found (p = 0.99). In a 3D plot, this gave a mean difference of 1.3 mm. The mean radius of the femoral head was of 22.5 mm (p = 0.6). CONCLUSIONS: CT-scan is as accurate and reliable as gold-standard techniques (motion and faro-arm). Locating FHC before and after hip arthroplasty would allow hip surgeons to determine and compare 3D orientation of the upper-end of femur: offset, height and anteversion.

Metasul vs Cerasul bearings: a prospective, randomized study at 9 years.

The aims of our study were to compare metal-on-metal (Metasul) and ceramic-on-ceramic (Cerasul) bearings and to evaluate the clinical and radiographic results of these 2 different hard-on-hard bearings. We conducted a prospective, randomized study on a series of 250 cementless primary total hip arthroplasties. The prostheses were similar in all aspects except for the bearing surfaces: 50% of Metasul bearing and 50% of Cerasul bearing. All the patients were evaluated both clinically and radiographically. No patient was lost to follow-up. Clinical outcomes in both groups were similar. Considering aseptic loosening as the end point for failure, the 9-year survival rate was 100% for Cerasul and 98.4% for Metasul. Neither bearing outperformed the other both radiographically and clinically. The overall 9-year survival rate was 99.2% and 97.6% in the Cerasul and Metasul groups, respectively.

Fractures of a sandwich ceramic liner at ten year follow-up.

PURPOSE: The aim of this study was to understand the causes of sandwich liner fractures implanted at our institution by evaluating the long-term results of this device. METHODS: We retrospectively assessed 143 patients (151 hips) consecutively operated upon in our department by the same senior surgeon between 1999 and 2001 and with a mean follow-up period of 9.9 years (range 8.5-11.5). The components used were Cerasul® sandwich ceramic liners within a cementless cup. Patient assessment was based on demographic factors (age, gender, body mass index), the clinical scores according to Devane (activity), the potential complications and a radiographic analysis from an anteroposterior pelvic radiograph (cup inclination). Revision cases and their cause were classified (implant fracture, loosening, dislocation, periprosthetic fracture). RESULTS: Five cases of liner fracture (3.7%) were observed at a mean seven year (4.5-8.5) follow-up. The risk factor for implant failure was found to be patient activity: the mean preoperative Devane score was 3.5 in the fracture group vs 2.6 in the control group (p = 0.008). Mean cup inclination was 52°. The survivorship analysis at ten years was 85% with revision as the endpoint. Prosthetic complications accounted for 8.6% of all 151 hips (fractures included): one case of aseptic loosening (0.7%), two cases of sepsis (1.4%), four cases of isolated dislocation (2.8%) and one case of recurrent dislocation (0.7%). CONCLUSIONS: Alumina sandwich liners remain a subject of concern since the increasing clinical follow-up period may predispose them to fatigue failure. This system has been abandoned in our department since 2005.