The benefit of dual mobility cup (DMC) for primary total hip arthroplasties (THA) is still controversial. This study aimed to compare 1) the complications rate, 2) the revisions rate, 3) the survival rate after monobloc DMC compared to large femoral heads (LFH) in primary THA. Between 2010 and 2019, 2,075 primary THA using cementless DMC or LFH were included. Indications for DMC were patients older than 70 years old or with high risk of dislocation. Every other patient received a LFH. Exclusion criteria were cemented implants, femoral neck fracture, a follow-up of less than one year. 1,940 THA were analyzed: 1,149 DMC (59.2%), 791 LFH (40.8%). The mean age was 73 ±9.2 years old in DMC group and 57 ±12 in LFH group. The complications and the revisions have been assessed retrospectively. The mean follow-up was 41.9 months ±14 [12–134]. There were significantly fewer dislocations in DMC group (n=2; 0.17%) compared to LFH group (n=8; 1%) (p=0.019). The femoral head size had no impact on the dislocations rate in LFH group (p=0.70). The overall complication rate in DMC (n=59; 5.1%) and LFH (n=53; 6.7%) were not statistically different (p=0.21). No specific complication was attributed to the DMC. In DMC group, 18 THA (1.6%) were revised versus 15 THA in LFH group (1.9%) (p= 0.71). There was no statistical difference for any cause of revisions in both groups. The cup aseptic revision-free survival rates at 5 years were 98% in DMC group and 97.3% in LFH group (p=0.78). Monobloc DMC had a lower risk of dislocation in a high-risk population than LFH in a low-risk population at the mid-term follow-up. There was no significant risk of specific complications or revisions for DMC in a large cohort. Monobloc DMC can be safely used in a selected high-risk population.
Twenty-five Regnauld’s procedures were performed in 20 patients with painful hallux valgus. This procedure involves the removal of proximal one-third of the proximal phalanx which is fashioned into a ‘hat-shaped graft’ and replaced as an osteochondral autogenous graft. The average age at operation was 56 years (range 39–76). After a mean follow-up of 3 years, 4 months (range 2.5–5.7 years), all the patients were assessed clinically and radiologically. The mean hallux valgus angle preoperatively was 29.3° (range 20–50°). At follow-up, a mean correction of 16.9° was obtained. In our study, 92% of patients were satisfied with the operation, but 8 patients (40%) showed progression of osteoarthritis of the first metatarsophalangeal joint. At 10 year follow up all these patient are satisfied with procedure and doing well. In view of the high incidence of degenerative changes in the first metatarsophalangeal joint, this procedure should be reserved for those patients over the age of 65 years or those with early osteoarthritic changes in the first metatarsophalangeal joint.
To assess the reliability of the pre-operative measurement methods used in the management of the hallux valgus deformity, five observers assessed 50 pre-operative standing foot radiographs on two occasions in order to assess the reliability of radiological hallux valgus assessment using the inter-metatarsal angle (IMA), hallux valgus angle (HVA) and joint congruency. Five published methods of angle measurements described by Hawkins, Venning and Hardy, Mitchell, Miller and Nestor were used. Kappa statistics were used to assess the reliability of the diagnosis of congruency. Regarding IMA and HVA, mean values between the methods were assessed by one-way ANOVA. The differences between the methods and observers were assessed by two-way ANOVA.
The mean IMA and HVA measurements varied significantly between methods on both occasions (p<
0.0001). Mitchell’s method had the lowest and Miller’s the highest mean values. Analysis of variance showed both method and observer variations were significant for IMA. But HVA measurements differed significantly only by observers.
The five different methods of measuring hallux valgus (HVA) and intermetatarsal angles (IMA) and the diagnosis of congruency of first MTP joint were studied on 50 pre-operative standing foot radiographs, to test if these methods were reliable and the results reproducible enough to be used in a treatment algorithm for hallux valgus. Analysis of variance (ANOVA) was used to examine the difference between the five methods and between the five observers. Kappa test was used to measure agreement in diagnosing congruency between two occasions. The mean IMA and HVA varied significantly (p<
0.00001). The ANOVA model showed that method and observer variations were both significant for IMA; there was no significant difference between measurement methods for HVA. Congruency had good (k=0.608) intraobserver and fair (k=0.261) interobserver reliability. A second IMA measurement will lie between 4.2° less and 4.6° more than the first IMA measurement 95% of the time. A second HVA measurement will lie between 6° less and 5.6° more than the first HVA measurement 95% of the time. Overall, there was no advantage to any of the measurement methods, although some observers were better than others. All methods had considerable inter- and intra-observer variability that makes these measurements unreliable.