Randomized controlled trial of intrathecal oxytocin on speed of recovery after hip arthroplasty.

ABSTRACT: Recovery from surgery is quicker in the postpartum period, and this may reflect oxytocin action in the spinal cord. We hypothesized that intrathecal injection of oxytocin would speed recovery from pain and disability after major surgery. Ninety-eight individuals undergoing elective total hip arthroplasty were randomized to receive either intrathecal oxytocin (100 µg) or saline. Participants completed diaries assessing pain and opioid use daily and disability weekly, and they wore an accelerometer beginning 2 weeks before surgery until 8 weeks after. Groups were compared using modelled, adjusted trajectories of these measures. The study was stopped early due to the lack of funding. Ninety patients received intrathecal oxytocin (n = 44) or saline (n = 46) and were included in the analysis. There were no study drug-related adverse effects. Modelled pain trajectory, the primary analysis, did not differ between the groups, either in pain on day of hospital discharge (intercept: -0.1 [95% CI: -0.8 to 0.6], P = 0.746) or in reductions over time (slope: 0.1 pain units per log of time [95% CI: 0-0.2], P = 0.057). In planned secondary analyses, postoperative opioid use ended earlier in the oxytocin group and oxytocin-treated patients walked nearly 1000 more steps daily at 8 weeks ( P < 0.001) and exhibited a clinically meaningful reduction in disability for the first 21 postoperative days ( P = 0.007) compared with saline placebo. Intrathecal oxytocin before hip replacement surgery does not speed recovery from worst daily pain. Secondary analyses suggest that further study of intrathecal oxytocin to speed functional recovery without worsening pain after surgery is warranted.

Characterizing Particle Evacuation in the Setting of Positive-pressure Body Exhaust Suit Using a Novel Gloving Technique.

The sterility of the gown-glove interface during total joint arthroplasty is a key factor in preventing contamination of the surgical field. To compare the potential of gown-glove interface contamination with a novel gloving technique versus standard gloving technique. We performed a study quantifying potential gown-glove interface contamination using two different gloving techniques. A 5 µm fluorescent powder simulated potential bacterial contamination. Each group gowned and gloved each hand using a modified technique versus traditional technique. Ultraviolet light was used to measure contamination at the gown-glove interface after performing a simulated surgery. The modified gloving technique did not statistically reduce the contamination at the gown-glove interface compared to the traditional gloving technique (p = 0.27). Despite using a gloving technique recently described as decreasing contamination, we noted contamination at the interface after performing a simulated surgery with a positive pressure exhaust suit. Further study is needed. (Journal of Surgical Orthopaedic Advances 30(3):166-169, 2021).

When computer-assisted knee replacement is the best alternative.

We studied whether computer-assisted surgery could properly align total knee arthroplasty when traditional instrumentation was not possible or appropriate. We identified 16 patients (18 knees) who we believed could not be treated using traditional instrumentation because of posttraumatic femoral deformity, retained femoral hardware, a history of osteomyelitis, or severe cardiopulmonary disease. Computer-assisted surgery was successfully used in 17 knees; we were unable to accurately register the hip in one morbidly obese patient. We judged the overall mechanical axis of the limb using computer-assisted surgery acceptable in 16 of 17 knees. One patient with a major posttraumatic biplane deformity had an overall mechanical axis in 4 degrees of varus. Computer-assisted navigation seemed helpful in difficult situations where accurate alignment remains crucial, yet traditional instrumentation is not applicable.

Synovial entrapment: a complication of posterior stabilized total knee arthroplasty.

BACKGROUND: We observed a complication of posterior stabilized total knee arthroplasty involving hypertrophy of tissue proximal to the patella associated with pain during active knee extension from 90 degrees of flexion. The purpose of this paper was to describe synovial entrapment and to determine if design features of the prosthesis predispose patients to the complication. METHODS: Between April 1990 and June 1999, we performed 459 consecutive posterior stabilized primary total knee arthroplasties using three prosthetic designs with different femoral intercondylar geometries. We identified twenty-six patients (twenty-seven knees) in whom arthroscopic débridement of the knee or open arthrotomy with débridement of the knee had been subsequently performed because of a diagnosis of synovial entrapment. We reviewed the records of these patients to identify the knee components that had been used and the symptoms and conditions that necessitated additional treatment. RESULTS: Symptoms (grating, crepitation, and pain with active knee extension from 90 degrees) necessitating subsequent débridement occurred in 13.5% (nineteen) of 141 knees treated with the Anatomic Modular Knee-Congruency implant, 3.8% (eight) of 212 treated with the Anatomic Modular Knee-Posterior Stabilized implant, and none of the 106 treated with the Press Fit Condylar Sigma-Posterior Stabilized implant. All patients had difficulty rising from a chair and climbing stairs; however, none had symptoms when standing or walking. No patient had a patellar clunk. The symptoms occurred at a mean of seven months after the arthroplasty in the patients with an Anatomic Modular Knee-Congruency implant and at a mean of twenty months after the arthroplasty in those with an Anatomic Modular Knee-Posterior Stabilized implant. Débridement of the frond-like hypertrophic synovial tissue at the distal aspect of the quadriceps tendon alleviated symptoms in all patients. No nodules were identified during the arthroscopy. CONCLUSIONS: Synovial entrapment is characterized by hypertrophic synovial tissue at the superior pole of the patella. Use of a posterior stabilized femoral component with a proximally positioned or wide femoral box is more likely to result in this complication.