RESUMO
Peripheral nerve injuries, associated with significant morbidity, can benefit from electrical stimulation (ES), as demonstrated in animal studies through improved axonal growth. This study combined the clinical gold standard of isograft repair in a rat model of sciatic nerve injury to evaluate the effects of intraoperative ES on functional tests and histology. Forty rats underwent a surgically induced gap injury to the right sciatic nerve and subsequent repair with an isograft. Half of these rats were randomly selected to receive 10 min of intraoperative ES. Functional testing, including response time to a heat stimulus and motor functional tests, were conducted. Histology of the sciatic nerves and gastrocnemius muscles were analyzed after 6 and 12 weeks of recovery. Rats that underwent ES treatment showed incremental improvements in motor function between weeks 2 and 12, with a significantly higher push-off response than the no-ES controls after 6 weeks. Although no differences were detected between groups in the sensory testing, significant improvements over time were noted in the ES group. Histology parameters, sciatic nerve measures, and gastrocnemius muscle weights demonstrated nerve recovery over time for both the ES and no-ES control groups. Although ES promoted improvements in motor function comparable to that in previous studies, the benefits of intraoperative ES were not detectable in other metrics of this rat model of peripheral nerve injury. Future work is needed to optimize sensory testing in the rodent injury model and compare electrical activity of collagen scaffolds to native tissue to detect differences.
RESUMO
Currently, many rehabilitation protocols for total hip replacements (THRs) include activity restrictions to prevent postoperative dislocation. There is increasing demand for more efficient and safe rehabilitation protocols. This randomized prospective study evaluates the need for hip restrictions following a modified anterolateral procedure. From 2004 to 2008, 81 patients seeking elective THRs were randomly assigned into a standard rehabilitation group or an early rehabilitation group. The standard group included restrictions to avoid hip flexion >90 degrees and avoidance of riding in a car for the first postoperative month. The early group had no flexion or car riding restrictions. Forty-three patients were in the standard group and 38 patients were in the early group. There were no significant demographic differences between the 2 groups. All patients completed the Short Form 12-question Health Survey and Harris Hip Score preoperatively and at 4 weeks, 1 month, 3 months, and 1 year postoperatively. The time-points at which the patient first drove and ambulated with a cane, without a cane, and without a limp were also collected. No incidents of dislocation occurred. Patients in the early group were faster to ambulate with only a cane (P=.03), without a cane (P<.001), and without a limp (P=.003). They also drove earlier (P=.02). Pace of recovery was the only significant difference between the 2 groups. The early rehabilitation protocol increases the pace of recovery compared to a pathway with hip precautions without increasing complications.
