Surgical Approach Does Not Influence Instability Risk in Revision Total Hip Arthroplasty.

BACKGROUND: Although the direct anterior (DA) approach has increased in popularity for primary total hip arthroplasty (THA), there is limited evidence regarding its use for revision THA. It is unknown whether the dislocation benefit seen in the primary setting translates to revision cases. METHODS: This retrospective review compared the dislocation rates of revision THA performed through DA versus postero-lateral (PL) approaches at a single institution (2011 to 2021). Exclusion criteria included revision for instability, ≥ 2 prior revisions, approaches other than DA or PL, and placement of dual-mobility or constrained liners. There were 182 hips in 173 patients that met the inclusion criteria. The average follow-up was 6.5 years (range, 2 to 8 years). RESULTS: There was a trend toward more both-component revisions being performed through the PL approach. There were no differences in dislocation rates between the DA revision and PL revision cohorts, which were 8.1% (5 of 72) and 7.5% (9 of 120), respectively (P = .999). Dislocation trended lower when the revision approach was discordant from the primary approach compared to cases where primary and revision had a concordant approach (4.9 versus 8.5%), but this was not statistically significant (P = .740). No significant differences were found in return to operating room, 90-day emergency department visits, or 90-day readmissions. However, the length of stay was significantly shorter in patients who had DA revisions after a primary PL procedure (P = .021). CONCLUSIONS: Dislocation rates following revision THA did not differ between the DA and PL approaches irrespective of the primary approach. Surgeons should choose their revision approach based on their experience and the specific needs of the patient.

A Comparison of Pavlik Harness Treatment Regimens for Dislocated But Reducible (Ortolani+) Hips in Infantile Developmental Dysplasia of the Hip.

BACKGROUND: Variation exists in the Pavlik harness (PH) treatment regimen for infantile developmental dysplasia of the hip (DDH). The purpose of this study was to determine if the daily PH wear duration (23 vs. 24 h) and frequency of follow-up visits affect the clinical and radiographic outcomes of infants with dislocated but reducible (Ortolani+) hips. METHODS: This study reviewed prospectively enrolled patients with DDH in a single center who presented at age <6 months with Ortolani+ hips and were treated with PH. Recommended daily PH wear duration (23 vs. 24 h) and the frequency of clinic visits in first 4 weeks after the initiation of PH treatment were analyzed. The clinical success (stable hip that did not require closed or open reduction or the use of an abduction orthosis) and radiographic success based on the acetabular index at 2-year follow-up were compared between different PH regimen groups. RESULTS: Sixty-two patients (74 hips, 53 females) with Ortolani+ hips had a mean age of presentation of 23±28 days (range, 4 to 128 d) and mean follow-up of 33.2±18.4 months (range, 8 to 85 mo). Overall clinical success rate of PH for Ortolani+ hips was 93% (69/74 hips) and radiographic success rate at 2 years was 84% (48/57 hips). There was no difference in clinical or radiographic success rate between the 23- and 24-hour wear groups (P>0.99, 0.73) or between hips assessed almost weekly compared with once or twice during the first 4 weeks of PH treatment (P>0.99 for both). CONCLUSIONS: The 23- versus 24-hour PH regimen and frequency of clinic visits in the first 4 weeks of PH treatment did not affect the clinical or radiographic success rate of Ortolani+ hips in infantile DDH. A strict weekly clinic visit and 24-hour PH regimen may not be necessary to obtain stable reduced hips in infants presenting <6 months of age with Ortolani+ hips. LEVEL OF EVIDENCE: Level III-therapeutic.

Single stage bilateral flexible intramedullary fixation of periprosthetic distal femur fractures.

We present a patient with bilateral Rorabeck II/Su III periprosthetic distal femur fractures treated successfully with bilateral single stage flexible intramedullary fixation. Flexible intramedullary fixation of Rorabeck II/Su III periprosthetic distal femur fractures provides the benefits of shorter operative time, lower blood loss, and preservation of bone stock compared to plate fixation and distal femur replacement. We suggest that for patients with similar injuries flexible intramedullary fixation can be a viable treatment option.

Single-stage bilateral distal femur replacement for traumatic distal femur fractures.

Treatment of periprosthetic distal femur fractures and comminuted intraarticular distal femur fractures with previous arthritis remains a difficult challenge for orthopedic surgeons. Previous case series have shown that distal femur replacement (DFR) can effectively compensate for bone loss, relieve knee pain, and allow for early ambulation in both of these fracture patterns. Owing to the typical low-energy mechanism of these injuries, a bilateral injury treated with DFR is rarely encountered. We present a patient with traumatic open left Rorabeck III/Su III periprosthetic distal femur fracture and closed right intraarticular distal femur fracture (AO fcation 33-C2) with end-stage arthrosis treated with single-stage bilateral DFR. We suggest that in patients with similar injuries, single-stage bilateral DFR can provide the benefits of early mobilization and accelerated recovery.

Quantitative assessment of synovitis in Legg-Calvé-Perthes disease using gadolinium-enhanced MRI.

A quantitative method to assess hip synovitis in Legg-Calvé-Perthes disease (LCPD) is not currently available. To develop this method, the areas of synovial enhancement on gadolinium-enhanced MRI (Gd-MRI) were measured by two independent observers. The volume of synovial enhancement was significantly increased in the initial and the fragmentation stages of LCPD (Waldenström stages I and II), with a persistence of synovitis into the reossification stage (stage III). The Gd-MRI method had high interobserver and intraobserver agreements and may serve as a useful method to monitor the effect of various treatments on hip synovitis in LCPD.