The benefit of the systematic revision of the acetabular implant in favor of a dual mobility articulation during the treatment of periprosthetic fractures of the femur: a 49 cases prospective comparative study.

INTRODUCTION: The SOFCOT symposium (2005) on periprosthetic fractures of the femur (PFFs) highlighted a high rate of dislocation (15.6% at 6 months) after change of prosthesis. So far, no study has ever proved the benefit of dual-mobility articulation during PFFs revisions. We conducted a comparative study on two prospective cohorts in order to (1) assess the influence of systematic acetabular revision in favor of a double mobility on dislocation rate (2) and in order to evaluate the rate of morbidity associated with this extra surgical procedure. HYPOTHESIS: A systematic replacement of the cup in favor of a dual-mobility articulation enables to reduce the dislocation rate in PFFs revisions without increasing morbidity. METHODOLOGY: We compared two prospective multicenter cohorts over a year (2005 and 2015) using the same methodology. Any fracture around hip prosthesis which occurred 3 months at least after surgery was included. Data collection was clinical and radiological on preoperative, intraoperative and 6 months after surgery. The 2015 "bipolar" group (n = 24) included patients who had a bipolar revision (both femoral and dual-mobility articulation). The 2005 "unipolar" group (n = 25) included patients who had only a femoral implant revision. Patients were comparable by age (p = 0.36), sex (p = 0.91), ASA score (p = 0.36), history of prosthetic revision (p = 1.00), Katz score (p = 0.50) and the type of fracture according to the Vancouver classification (p = 0.55). RESULTS: There was a 4% rate of dislocation in the "bipolar group" while there was 21% rate of dislocation in the "unipolar group" (8% of recurrent dislocation) (p = 0.19). The rate of all-cause complications 6 months after surgery was not significantly different (p = 0.07): 12.5% in the 2015 "bipolar" cohort (one dislocation, one non-symptomatic cup migration and one pseudarthrosis of the major trochanter) versus 35% in the "unipolar" cohort (5 dislocations, 1 major trochanter fracture and 1 femur pseudarthrosis, 1 secondary displacement associated with a superficial infection). The surgical revision after 6 months was not significantly different (1/23 or 4% vs. 4/25 or 16%, p = 0.35). CONCLUSION: We confirm the low rate of dislocations after fitting a dual-mobility cup in case of revision of the femoral side in case of periprosthetic femoral fracture, as well as the need for additional cases to be carried out upon further studies to significantly confirm the interest of preventing instability after femoral revision.

High-impact sport after hip resurfacing: The Ironman triathlon.

BACKGROUND: Returning to high-impact sport is an increasingly frequent functional demand following hip replacement. The literature, however, is sparse on the subject and nonexistent regarding triathlon. We therefore conducted a retrospective study of hip resurfacing in triathlon players, to determine: (1) whether it is possible to return to this kind of sport; (2) if so, whether it is possible to return to the same level; and (3) how a resurfaced hip behaves under these conditions. HYPOTHESIS: Hip resurfacing allows return to competition level in long-distance triathlon. MATERIAL AND METHODS: A single-center single-operator retrospective study included patients undergoing hip resurfacing with the Conserve Plus implant inserted through a posterolateral approach, who had ceased long-distance triathlon practice due to osteoarthritis of the hip. Fifty-one of the 1688 patients undergoing resurfacing during the inclusion period were long-distance triathlon players. RESULTS: The series comprised 48 patients: 51 implants; 43 male, 5 female; mean age, 44.8 years (range, 28.2-58.9 years). At a mean 4.7 years' follow-up (range, 2.2-7.6 years), all clinical scores showed significant improvement; Merle d'Aubigné and Harris scores rose respectively from 12.3 (5-16) and 42 (37-56) preoperatively to 17.5 (13-18) and 93.2 (73-100) (P<0.001). There were no cases of dislocation or implant revision. Forty-five patients returned to sport (94%). Rates of return to swimming, cycling and running were respectively 38/48 (79%), 41/48 (85%) and 33/48 (69%). Preoperatively, all patients had taken part in at least 1 competition: 29 with distance=70.3km and 19 with distance=140.6km. At follow-up, 28 patients had taken part in an Ironman competition: 21 with distance=70.3km and 7 with distance=140.6km. Mean competition performance did not differ between pre and postoperative periods. DISCUSSION: Return-to-sport rates were good following hip resurfacing. Non-impact sports (swimming, cycling) predominated postoperatively, whereas the rate of impact sport (running) diminished. Return to competition-level sport (extreme triathlon) was possible for 28/48 patients (58%). Implant survival seemed unaffected by this high-impact sports activity at a mean 4.7 years' follow-up. LEVEL OF EVIDENCE: IV, retrospective, non-controlled.

Does primary total knee arthroplasty for acute knee joint fracture maintain autonomy in the elderly? A retrospective study of 21 cases.

INTRODUCTION: Due to poor results and failure encountered in osteosynthesis of peri-articular fracture of the knee, arthroplasty may be suggested to osteopenic elderly subjects. All osteosynthesis techniques entail loss of independence and are associated with elevated mortality. No studies definitively establish better management of such fractures. HYPOTHESIS: Total arthroplasty provides better autonomy after peri-articular fracture of the knee. MATERIAL AND METHOD: Seventy-nine patients aged over 65years were operated on for peri-articular fracture of the knee between April 2008 and March 2013. In 21 cases, treated by a single surgeon, total knee arthroplasty was performed in view of osteopenia or osteoarthritis. Mean age was 79years (range, 68-96years). There were 10 distal femoral and 11 proximal tibial fractures. Mean follow-up was 31months (range, 9-68months). Cases of pathologic fracture, failed osteosynthesis and non-operative management were excluded. All patients showed severe osteopenia on radiology and half already had advanced osteoarthritis. RESULTS: One-year mortality was 14%. At last follow-up, the revision rate was 9.5%. Fifteen patients were followed up. Mean Parker score fell from 7.2 (range, 2-9) preoperatively to 4.6 (range, 0-9) at last follow-up, indicating loss of independence. At follow-up, mean IKS score was 116.6 (range, 0-192) with mean IKS knee score of 78.4 (range, 0-100) and IKS function score of 38.2 (range, 0-100). Mean Oxford score was 36/60 (range, 18-53). Global IKS and IKS function scores were significantly better in case of ASA-2 than ASA-3 (P<0.05). There was no difference between femoral and tibial fractures in terms of IKS or Oxford score or loss of independence. DISCUSSION: Total knee arthroplasty can be considered for peri-articular fracture of the knee in osteopenic geriatric patients. Although surgical revision was less frequent than after osteosynthesis and resumption of weight-bearing was immediate, autonomy was still impaired. Mortality was comparable to other reports. LEVEL OF EVIDENCE: IV, retrospective study.

Technique to treat iliopsoas irritation after total hip replacement: Thickening of articular hip capsule through an abridged direct anterior approach.

Iliopsoas irritation due to acetabular cup component impingement following total hip arthroplasty (THA) is usually treated by infiltration or by distal iliopsoas tenotomy in case of recurrence; however, this can result in an active flexion deficit of the thigh. To prevent this complication, we developed an original technique that we performed between 2012 and 2014 in patients with recurrent impingement following extraarticular corticosteroid injections. This included 5 patients (mean age: 64 [53-75] years old) in whom we performed an ambulatory bursectomy by the Hueter approach and placed a polyglactin 910 (Vicryl™) mesh plate on the entire anterior hip capsule. After a mean follow-up of 12months (9-29months), anterior pain had decreased in all patients with improvement and an increase in the Oxford-12 (mean: 15 points [10-19]), Merle d'Aubigné (mean: 2.5 points [1-5]) and Harris (mean: 18 points [10-29]) scores. No flexion deficits were observed. An infected postoperative hematoma had to be drained but was cured at follow-up. This simple procedure provides satisfactory results and preserves THA function. It does not jeopardize future procedures and is an alternative option in case of unsuccessful conservative treatment.

Computed tomography evaluation of hip geometry restoration after total hip resurfacing.

BACKGROUND: Anatomic reconstruction of the hip is among the main requirements for hip arthroplasty to be successful. Resurfacing arthroplasty may improve replication of the native joint geometry but has been evaluated only using standard radiographs. We therefore performed a computed tomography (CT) study to assess restoration of hip geometry after total hip resurfacing (HR), comparatively with the non-operated side. HYPOTHESIS: HR does not change native extra-medullary hip geometry by more than 5mm and/or 5°. PATIENTS AND METHODS: CT was used to evaluate unilateral HR in 75 patients with a mean age of 52.2years (range, 22-67years). The normal non-operated side served as the control in each patient. Mean follow-up was 2.5years (range, 1.9-3.1years). The primary evaluation criteria were femoral offset (FO) and femoral neck anteversion (FNA) and the secondary criteria were cup inclination angle, cup anteversion angle, and lower-limb length. RESULTS: FO showed a non-significant decrease (mean, -2.2mm; range, -4.5 to +3.7mm). FNA was preserved, with a difference of less than 2° at last follow-up versus the preoperative value. Cup measurements showed a mean anteversion angle of 24.8° (0.9-48.6) and mean inclination angle of 44.1° (32.1-56.3); corresponding values for the native acetabulum were 38.9° (20.5-54.8) and 24.8° (4.8-33.6). The residual lower-limb length discrepancy was less than 1mm (mean, -0.04mm [-1.2 to +1.6mm]). The mean angle between the femoral implant and the femoral neck axis was 5.4° of valgus. DISCUSSION: Our results show that HR accurately restored the native extra-medullary hip geometry. LEVEL OF EVIDENCE: III, prospective diagnostic case-control study.