Radiographic Assessment of Guided Growth: The Correlation Between Screw Divergence and Change in Anatomic Alignment.

BACKGROUND: Assessment of changes in anatomic alignment following guided growth traditionally utilizes full-length standing radiographs which subjects patients to larger radiation doses than does a single anteroposterior radiograph of the knee. In an effort to minimize radiation exposure, the present study sought to determine whether changes in screw divergence (SD) of the 2-hole tension band plate used for hemiepiphysiodesis reliably predicts change in alignment. METHODS: A retrospective review was conducted involving all patients with genu varum or genu valgum treated with hemiepiphysiodesis at a single institution. Preoperative anatomic alignment of the femur, using anatomic lateral distal femoral angle (aLDFA) and anatomic femoral-tibial angle (aTFA), and intraoperative divergence of hemiepiphysiodesis screws were compared with postoperative imaging. Linear regression analysis determined the relationship between changes in SD and changes in alignment, and multivariate regression analysis explored the relationship between the angular changes being measured and various demographic factors. RESULTS: Linear regression analysis revealed that for every 1 degree change in SD there was a resultant 1.80 degrees of change in aTFA and 2.11 degrees of change in aLDFA. Change in aTFA is predicted by the equation: [INCREMENT]aTFA=0.41×|[INCREMENT]SD|+1.39. The change in aLDFA was predicted by the equation [INCREMENT]aLDFA=0.27×[INCREMENT]SD+1.84 with a R2 of 0.31. [INCREMENT]aTFA and [INCREMENT]SD had a correlation coefficient of 0.68 (95% confidence interval, 0.54-0.78.) [INCREMENT]aLDFA and [INCREMENT]SD had a correlation coefficient of 0.56 (95% confidence interval, 0.42-0.68). [INCREMENT]SD and sex were the only 2 independent predictors for [INCREMENT]aLDFA and [INCREMENT]aTFA as determined by multivariate regression analysis. CONCLUSION: Change in coronal plane anatomic alignment in patients being treated for genu valgum or genu varum with hemiepiphysiodesis can be reasonably estimated by measuring the change in SD. Therefore, when following patients postoperatively, focal radiographic imaging of the knee can be utilized in lieu of standing full-length limb radiographs to limit radiation to the pelvis in this sensitive patient population. LEVEL OF EVIDENCE: Level III-retrospective comparative study.

"Outpatient"-Same-calendar-day Discharge Hip and Knee Arthroplasty.

As the length of stay for hip and knee arthroplasty has decreased over the years, "outpatient," or same-calendar-day discharge has become increasingly common. Outpatient arthroplasty offers several possible benefits over traditional inpatient arthroplasty, including potential for cost reductions, faster rehabilitation, improved patient satisfaction, and reduced reliance on hospital resources. Despite these possible benefits, concerns remain over feasibility and patient safety. To date, multiple studies have demonstrated that, for select patients, "outpatient" hip and knee arthroplasty can be safe and effective and yield complication and readmission rates similar to inpatient procedures at potentially significant cost savings. Successful outpatient pathways have emphasized careful patient selection, detailed patient education, enlistment of strong social support, utilization of multimodal analgesia and strong "episode ownership," and involvement on behalf of the surgical team. As outpatient hip and knee arthroplasty becomes increasingly common, continued investigation into all aspects of the surgical episode is warranted.

Management of Lower Extremity Long-bone Fractures in Spinal Cord Injury Patients.

The AO classification system, used as a guide for modern fracture care and fixation, follows a basic philosophy of care that emphasizes early mobility and return to function. Lower extremity long-bone fractures in patients with spinal cord injury often are pathologic injuries that present unique challenges, to which the AO principles may not be entirely applicable. Optimal treatment achieves healing without affecting the functional level of the patient. These injuries often result from low-energy mechanisms in nonambulatory patients with osteopenic bone and a thin, insensate soft-tissue envelope. The complication rate can be high, and the outcomes can be catastrophic without proper care. Satisfactory results can be obtained through various methods of immobilization. Less frequently, internal fixation is applied. In certain cases, after discussion with the patient, amputation may be suitable. Prevention strategies aim to minimize bone loss and muscle atrophy.