Range of Motion at Discharge Predicts Need for Manipulation following Total Knee Arthroplasty.

Stiffness following total knee arthroplasty (TKA) is a common complication that can result in unsatisfactory outcomes. Manipulation under anesthesia (MUA) has been widely employed to treat this problem. It is uncertain whether an association exists between range of motion (ROM) at discharge and need for MUA following primary TKA.A retrospective review of an institutional joint registry identified cases of primary TKA performed by three surgeons at a single institution over a 22-month period. A logistic regression model was used to examine the association between ROM at discharge and subsequent MUA controlling for confounding variables related to patient demographics and perioperative details. Of the 1,546 cases identified, 113 (7.3%) cases underwent subsequent MUA. As discharge ROM increased, manipulation rates decreased. Patients with discharge flexion <65 degrees were more likely to undergo MUA than those with flexion >90 degrees (odds ratio [OR] = 17.57, 95% confidence interval [CI] [7.97, 38.73], p < 0.0001). The largest differential in odds of MUA was observed between the <65 degrees at discharge group (OR = 17.57) and the 65 ≤ 75 degrees at discharge group (OR = 7.89). At discharge ROM of 80 ≤ 90 degrees of flexion, patients had more than a twofold increase in odds of MUA relative to those in the >90 degrees group (OR = 2.22, 95% CI [1.20, 4.10], p = 0.011). The results of this study suggest that there is an association between lower ROM at discharge and greater risk of MUA post primary TKA. Counseling patients in regard to discharge ROM and associated risk of MUA may optimize gains in ROM during recovery.

Pinnacle Ultamet metal-on-metal total hip arthroplasty survivorship: average 10-year follow-up.

BACKGROUND: It is unclear whether a connection exists between femoral head size, offset, neck length, and cup abduction angles, and rate of revision in metal-on-metal (MoM) total hip arthroplasty (THA) implant systems. METHODS: A retrospective review of MoM THA completed by a single surgeon with a single implant between 2003 and 2008 was conducted. Patient demographics, implant data, radiographs, and revision details were collected at follow-up. Incidence rates for revision and osteolysis were calculated in regard to the femoral head size, stem offset, neck length, and cup abduction angles. RESULTS: Six hundred and ninety two THAs were identified, with 79% of patients returning for a median follow-up of 10.3 years (interquartile range = 6.0-12.3). The median time to revision was 7.5 years (interquartile range = 5.3-9.9) among 27 total revision surgeries. The overall incidence rate of revision was 5.4 revisions per 1000 person-years, 3.0 revisions per 1000 person-years for adverse local tissue reaction. Hips with a cup abduction angle of ≤40° had revisions at nearly twice the rate of those with an angle of 41°-50° (incidence rate ratio = 1.98, 95% confidence interval: 0.92, 4.29). Hips with a 9 mm neck length had an increased rate of revision (incidence rate ratio = 5.94, 95% confidence interval: 1.33, 26.55) relative to those with a neck length of 0 mm. Rates of osteolysis were similar between implants of different head sizes, neck lengths and cup abduction angles. CONCLUSIONS: MoM implant systems with longer necks and smaller cup abduction angles may lead to increased need for revision. Results from this study suggest a need for closer long-term follow-up of MoM THA systems.