Faculty Bibliography

Cephalomedullary devices (CMN) have become an increasingly popular for treatment of intertrochanteric hip fractures compared to sliding hip screw and side plate (SHS) devices. Failed fixation is often treated with conversion total hip arthroplasty (THA). We performed a multi-institutional study in which 60 patients with SHS devices and 31 patients with CMN devices were converted to THA. Harris Hip Score improved from 41.6 preoperatively to 83.6 at final follow-up in the SHS group and from 41.6 to 78.6 in the CMN group, with no significant difference between the groups (P=0.23). However, the complication rate in converted CMN patients was significantly higher at 41.9% compared with 11.7% (P=0.001) in converted SHS patients. Prior fixation with CMN may be associated with significantly higher complication rates during conversion.

AIM: To track the short-term neck narrowing changes in Birmingham metal-on-metal hip resurfacing (MOMHR) patients. METHODS: Since 2001, the Center for Hip and Knee Replacement started a registry to prospectively collect data on hip and knee replacement patients. From June 2006 to October 2008, 139 MOMHR were performed at our center by two participate surgeons using Birmingham MOMHR prosthesis (Smith Nephew, United States). It is standard of care for patients to obtain low, anteriorposterior (LAP) pelvis radiographs immediately after MOMHR procedure and then at 3 mo, 1 year and 2 year follow up office visits. Inclusion criteria for the present study included patients who came back for follow up office visit at above mentioned time points and got LAP radiographs. Exclusion criteria include patients who missed more than two follow up time points and those with poor-quality X-rays. Two orthopaedic residency trained research fellows reviewed the X-rays independently at 4 time points, i.e., immediate after surgery, 3 mo, 1 year and 2 year. Neck-to-prosthesis ratio (NPR) was used as main outcome measure. Twenty cases were used as subjects to identify the reliability between two observers. An intraclass correlation coefficient at 0.8 was considered as satisfied. A paired t-test was used to evaluate the significant difference between different time points with P < 0.05 considered to be statistically significant. RESULTS: The mean NPRs were 0.852 +/- 0.056, 0.839 +/- 0.052, 0.835 +/- 0.051, 0.83 +/- 0.04 immediately, 3 mo, 1 year and 2 years post-operatively respectively. At 3 mo, NPR was significantly different from immediate postoperative X-ray (P < 0.001). There was no difference between 3 mo and 1 year (P = 0.14) and 2 years (P = 0.53). Femoral neck narrowing (FNN) exceeding 10% of the diameter of the neck was observed in only 4 patients (5.6%) at two years follow up. None of these patients developed a femoral neck fracture (FNF). CONCLUSION: Femoral neck narrowing after MOMHR occurred as early as 3 mo postoperatively, and stabilized thereafter. Excessive FNN was not common in patients within the first two years of surgery and was not correlated with risk of FNF.

The effects of altering patients' femoral offset (FO) during total hip arthroplasty on postoperative pain and function have not been well described. This study compared clinical outcomes as assessed by the Short Form 12 Health Survey and Western Ontario and McMaster University Osteoarthritis Index between patients who had their FOs restored to varying degrees (compared to the contralateral normal hip [CL]). We retrospectively measured postoperative FOs on standard anteroposterior pelvis radiographs and compared to the CL. Patients were categorized into one of 3 groups: decreased offset (< -5 mm compared to CL), normal offset (between -5 and +5 mm), and increased offset (> +5 mm). The decreased offset group exhibited Western Ontario and McMaster University Osteoarthritis Index Physical Function scores that were less than those of the normal offset and increased offset groups (72.03, 82.23, and 79.51, respectively [P = .019]). In conclusion, reducing a patients' native FO led to inferior functional outcome scores.

This article quantifies pain differences in the immediate postoperative period between patients undergoing total hip arthroplasty (THA) and metal-on-metal hip resurfacing (MoMHR). Patients less than 65 years old indicated for either a primary MoMHR or THA were screened for consent. A total of 51 patients completed the study. Controlling for confounding factors, patients having MoMHR experienced significantly less pain at 24 hours than patients having THA. The MoMHR cohort experienced a significantly shorter length of stay than the THA cohort. MoMHR shows a significantly lower pain level at 24 hours than THA and a significantly earlier discharge.

This study compared outcomes as assessed by 12-item Short-Form Health Survey (SF-12) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) between patients who underwent unicompartmental (UKA) and patients who underwent total knee (TKA) arthroplasty. We prospectively collected preoperative demographic and SF-12 and WOMAC data on 128 TKAs and 70 UKAs. Postoperatively, SF-12 and WOMAC outcomes were recorded during annual follow-up visits. At baseline, patients who underwent UKA had a higher Charlson Comorbidity Index than patients who underwent TKA; otherwise, preoperative characteristics were similar. At a mean follow-up of 3.0 years for UKA and 2.9 years for TKA, patients who underwent UKA reported higher SF-12 physical component and mental component scores and WOMAC pain/stiffness/physical function scores (confirmed with multivariate analysis). Furthermore, patients who underwent UKA had significantly larger improvements in both SF-12 outcomes and WOMAC pain and physical function scores from baseline than did patients who underwent TKA.

The purpose of this study was to compare short-term clinical outcomes between total hip arthroplasty (THA) and total knee arthroplasty (TKA) patient cohorts, adjusting for confounding variables including age, sex, body mass index, operative time, length of stay, and preoperative Western Ontario and McMaster Universities and 12-Item Short-Form Health Survey. A total of 349 patients who met inclusion and exclusion criteria created 2 cohorts: THA, 194, and TKA, 155, for statistical analysis via multiple regression and analysis of covariance measures. Outcome measures included Western Ontario and McMaster Universities and 12-Item Short-Form Health Survey data, collected prospectively at baseline and 2 years of follow-up. The current study showed that baseline characteristics of TKA patients have more factors with negative effect on postoperative outcome than THA. However, despite controlling for the possible confounding effect of these variables, THA patients experienced a significantly better functional outcome than TKA patients.

Total knee arthroplasty (TKA) can lead to substantial blood loss. To avoid the high costs of autologous blood predonation programs and efficiently allocate limited blood resources, we sought to identify preoperative and intraoperative factors associated with allogeneic blood transfusion (AllTx) after primary TKA and, subsequently, develop a model to predict patients who will require AllTx. We analyzed 31 independent variables in 644 primary unilateral TKAs without autologous blood predonation for requirement of AllTx. Seventy-one procedures (11.0%) required AllTx. Age, comorbid anemia, preoperative hemoglobin concentration, and surgical time were significant predictors for requiring AllTx. When applied to an independent cohort, our model for predicting the need for AllTx after TKA was 90% sensitive and 52.5% specific.

BACKGROUND: Intraarticular hip disease is commonly acknowledged as a cause of ipsilateral knee pain. However, this is based primarily on observational rather than high-quality evidence-based studies, and it is unclear whether ipsilateral knee pain improves when hip disease has been treated. QUESTIONS/PURPOSES: We asked whether (1) hip disease was associated with preoperative ipsilateral knee pain and (2) ipsilateral knee pain would improve after hip arthroplasty. PATIENTS AND METHODS: We retrospectively assessed knee pain in 255 patients who underwent hip arthroplasties between 2006 and 2008. The WOMAC pain score of each joint was the primary outcome measure, which was obtained prospectively before surgery and at 3 months and 1 year postoperatively. Of the 255 patients, 245 (96%) had followup data obtained at 3 months or 1 year. RESULTS: Preoperatively, ipsilateral knee pain was observed more frequently than contralateral knee pain (55% versus 18%). Preoperative ipsilateral knee pain scores were worse than contralateral knee pain scores (mean, 80 versus 95). Ipsilateral knee pain improved at 3 months and 1 year. When compared with the scores for contralateral knee pain at 3 months (95) and 1 year (96), there were no differences between knees. CONCLUSIONS: Our observations suggest hip disease is associated with ipsilateral knee pain and that it improves after hip arthroplasty. This should be considered during preoperative evaluation for patients with hip and knee pain. LEVEL OF EVIDENCE: Level III, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.

AIM: To identify factors that affect patient response rates to preoperative functional surveys in hip and knee arthroplasty patients. METHODS: From May 2008 to March 2009, 247 patients were scheduled more than 4 wk in advance for hip or knee arthroplasty by one of two participating surgeons at our center. A personalized questionnaire comprised of the Short Form 12 (SF-12) and Western Ontario and McMaster Universities (WOMAC) Index was mailed to patients at random time points ranging from 7 to 101 d prior to surgery. Nine independent factors were documented prospectively, including age, gender, ethnicity, marital status, type of surgery, surgeon, days prior to surgery (DPS) of survey mailing, WOMAC score and SF-12 score. The date of the completed survey receipt was also documented. For non-responders, the surveys were completed with the research team at the hospital upon admission. Multivariate regression and chi(2) analysis were performed with Statistical Analysis Software software. RESULTS: DPS was the only factor that affected patient response. Mailing surveys 26 d to 31 d prior to surgery dates led to a peak response rate of 80% that was significantly higher (P < 0.023) than response rates for patients who were mailed their surveys /= 32 d prior to surgery (55%). No other factors, including preoperative WOMAC and SF-12 scores, significantly influenced response behavior. CONCLUSION: The DPS was independently the most significant predictor of response rates for pre-operative functional data among patients scheduled for hip and knee arthroplasty.