Brian J. McGrory

Effect of femoral offset on range of motion and abductor muscle strength after total hip arthroplasty

At a minimum of one year after operation, we studied 64 patients with 86 total hip arthroplasties (THA) by standard anteroposterior hip and pelvic radiographs and measurement of range of motion and of isometric abduction strength. The femoral offset correlated positively with the range of abduction (p = 0.046). Abduction strength correlated positively with both femoral offset (p = 0.0001) and the length of the abductor lever arm (p = 0.005). Using multiple regression, abduction strength correlated with height (p = 0.017), gender (p = 0.0005), range of flexion (p = 0.047) and the abductor lever arm (p = 0.060). Our findings suggest that greater femoral offset after THA allows both an increased range of abduction and greater abductor strength.

Acute fractures and dislocations of the cervical spine in children and adolescents.

We reviewed the records of 143 patients, two months to fifteen years old, who were seen at the Mayo Clinic between 1950 and 1991 because of an injury to the cervical spine. There was a clear demarcation between the characteristics of the injury of two age-groups. Children who were less than eleven years old had fewer injuries as a group, were most often injured in falls, tended to have a predominance of ligamentous injuries of the cephalic portion of the cervical spine, and had a high rate of mortality as a consequence of injury to the spinal cord. Children who were eleven through fifteen years old had more injuries as a group, were most often injured during sports and recreational activities, had a higher male-to-female ratio, were more frequently injured in the caudal portion of the cervical spine, and had a pattern of injury similar to that of adults. The age and sex-adjusted incidence was 7.41 per 100,000 population per year.

Arthrodesis of the cervical spine for fractures and dislocations in children and adolescents. A long-term follow-up study.

Forty-two patients who had had an arthrodesis for instability of the cervical spine resulting from trauma were followed clinically for a minimum of seven years (median, seventeen years and six months). The ages of the patients at the time of the injury ranged from one year and eleven months to fifteen years and eleven months. On the basis of a new post-traumatic neck score, which includes an assessment of pain, mobility, neurological status, and function, thirty-two patients (76 per cent) had an excellent result, six (14 per cent) had a good result, and four (10 per cent) had a fair result. No patient had a poor result. There was no notable deterioration of the clinical result with an increased duration of follow-up. Current radiographs of the cervical spine in flexion and extension were available for thirty-one (74 per cent) of the forty-two patients. There was no change in stability, deformity, or the fusion mass after healing or with an increased duration of follow-up, but there was a significant increase in osteoarthrotic changes in the unfused segments of the cervical spine after an increased duration of follow-up (p = 0.0001). Complications included spontaneous extension of the fusion mass in sixteen patients (38 per cent), mild pain or dysesthesias at the iliac-crest donor site in six patients (14 per cent), superficial infection at a bone-graft donor site in one patient (2 per cent), an incorrect level of arthrodesis in one patient (2 per cent). One patient had instability secondary to juvenile rheumatoid arthritis, which developed after treatment of the original injury, and she needed a reoperation. We concluded that spinal arthrodesis for fractures and dislocations of the cervical spine in children and adolescents can be accomplished safely, with an acceptable clinical outcome, a low rate of complications, and minimum morbidity after long-term follow-up. Pain, neurological status, and function do not change markedly, but mobility may decrease with an increased duration of follow-up. Our patients had a decrease in mobility, associated with an increase in osteoarthrotic changes, as seen on radiographs (p = 0.05).

Obesity and total joint arthroplasty. A literature based review

The prevalence of obesity in the population is unlikely to decline, and is likely to contribute to the increasing demand for hip or knee arthroplasty. Conflicting data exist on the risk and benefits of total joint arthroplasty in obese patients. The purpose of this manuscript is to define and identify areas of concern for obese patients undergoing total joint arthroplasty. A workgroup of total joint arthroplasty surgeons from the American Association of Hip and Knee Surgeons (AAHKS) was tasked with identifying key questions regarding obesity and total joint arthroplasty. The workgroup evaluated the available literature and sought to create a review regarding obesity and total joint arthroplasty to complement and guide the surgeon-patient discussion in addition to identifying areas of future research.

Patients' Concerns Prior to Undergoing Total Hip and Total Knee Arthroplasty

OBJECTIVE To document and examine the concerns patients have prior to undergoing primary total hip or total knee arthroplasty in a tertiary care center or an orthopedic private practice group. PATIENTS AND METHODS In this prospective survey, 136 patients from a tertiary care center and 130 from an orthopedic private practice group completed a questionnaire covering 54 items regarding their concerns prior to undergoing primary total hip or total knee arthroplasty. Patients responded on a visual analog scale, and concern was ranked by mean responses (1, not concerned at all; 2, somewhat concerned; 3, very concerned; or 4, extremely concerned). RESULTS Responses to only 6 items averaged scores higher than 1.9: pain immediately after the surgery (2.07), length of recovery (2.07), ability to walk as much as you wish (2.03), ability to return to recreational activities (1.97), ability to go up and down stairs (1.94), and risk of getting acquired immunodeficiency syndrome from a transfusion (1.92). Older patients (> or = 65 years) were less concerned than younger patients (< 65 years) in 34 of the 54 questions asked. Women were more concerned than men in 19 of the 54 questions asked. CONCLUSION These data provide information that will be helpful in preoperative patient discussions and in development of educational materials for patients undergoing total hip or total knee arthroplasty.

Correlation of patient questionnaire responses and physician history in grading clinical outcome following hip and knee arthroplasty: A prospective study of 201 joint arthroplasties

Questionnaires are commonly used in orthopaedic outcome studies. This study sought to determine if responses to a simple standardized questionnaire correlated with responses obtained during a physician interview in evaluation of clinical outcome following hip and knee arthroplasty. One hundred sixty-two patients with 201 hip and knee arthroplasties were asked to fill out a questionnaire prior to returning for routine follow-up evaluation. There was a highly significant correlation (P < .0001, r = .74) between scores calculated from patient responses on the questionnaire and those calculated from responses recorded during the subsequent physician visit. There was no significant difference between patient and physician clinical hip scores, but physicians gave significantly higher knee scores than patients for both long- ( > 4.5 years, P < .05) and short-term ( < or = 4.5 years, P < .0001) follow-up periods; however, 97% of patient responses were within one grade of physician-recorded answers to the same questions. Eight and one-half percent of scores differed in overall evaluation from good-excellent to fair-poor categories. This study both validates and defines more clearly the limitations of questionnaires for follow-up evaluation of clinical results following total hip and knee arthroplasty.

Current practices of AAHKS members in the treatment of adult osteonecrosis of the femoral head.

BACKGROUND There is currently no standardized protocol for evaluating and treating osteonecrosis of the femoral head in adults in the United States. We sought to understand current treatment practices of a group of surgeons who commonly treat this disease to determine if there was agreement on some aspects of care. METHODS We designed a two-staged mixed-mode (mailed and faxed) sixteen-question self-administered descriptive survey questionnaire to be sent to all 753 active members of the American Association of Hip and Knee Surgeons (AAHKS). The survey design was based on Dillmans survey research methodology, and the questionnaire included hypothetical clinical scenarios based on the Steinberg classification system. The responses elucidated the opinions and treatment preferences of high-volume arthroplasty surgeons who treat adult patients with osteonecrosis of the femoral head. RESULTS Of the 753 active members of the AAHKS, 403 (54%) responded to the questionnaire. Total hip replacement was reported to be the most frequent intervention for treatment of postcollapse (Steinberg stage-IIIB, IVB, V, and VI) osteonecrosis; core decompression was reported to be the most commonly offered intervention for symptomatic, precollapse (Steinberg stage-IB and IIB) osteonecrosis. Less frequently offered treatments included nonoperative management, osteotomy, vascularized and non-vascularized bone-grafting, hemiarthroplasty, and arthrodesis. CONCLUSIONS The care of adults with osteonecrosis of the femoral head varies among American orthopaedic surgeons specializing in hip and knee surgery. A consensus may evolve with a continued concerted effort on the part of interested surgeons, but it will require randomized, controlled, prospective studies of treatment of each stage of the disease and collaborative multicenter studies. LEVEL OF EVIDENCE Therapeutic Level V.

A High Prevalence of Corrosion at the Head–Neck Taper with Contemporary Zimmer Non-Cemented Femoral Hip Components

Mechanically assisted crevice corrosion (MACC) occurs at metal/metal modular junctions in which at least one of the components is fabricated from cobalt-chromium alloy and may lead to adverse local tissue reaction (ALTR) in patients with metal-on-polyethylene (MoP) total hip arthroplasty. This type of reaction has been previously described in hips with head/neck modularity, but the prevalence is unknown. We found a prevalence of 1.1 percent in a consecutive series of 1356 contemporary Zimmer non-cemented femoral hip components followed for a minimum of 2years. The average time to presentation was 3.7years (range, 9-105months); delay in treatment led to irreversible soft tissue damage in three patients. We recommend usage of ceramic heads until this problem is further understood.

Correlation of Measured Range of Hip Motion Following Total Hip Arthroplasty and Responses to a Questionnaire

Twenty-eight patients (with 30 primary and 8 revision total hip arthroplasties) completed a standardized questionnaire containing the Western Ontario and McMaster Universities (WOMAC) osteoarthritis index and Harris hip score questions prior to an office visit a minimum of 1 year after surgery. The range of hip motion measured by an orthopaedic surgeon was compared with the responses to questions on stiffness and function as well as with global scores in the WOMAC osteoarthritis index. Patient responses to the questions asking if they could cut their toenails on the operated side and the Harris hip score question asking if they could put on socks and tie a shoe correlated significantly with postoperative hip motion (P < .005). The WOMAC global pain and stiffness scores did not correlate with range of motion. The WOMAC physical function score correlated significantly only with hip flexion (P < .05). Of the WOMAC physical function questions, difficulty bending to pick an object off the floor (P < .05) and getting on and off the toilet (P < .05) correlated with the sum of the range of motion in all planes and weighted Harris hip score range of motion calculation. These data suggest that the points allocated in the Harris hip score for range of motion can be estimated reasonably accurately from questionnaire or phone response to a series of questions on a standardized questionnaire. The question on ability to cut toenails or the Harris hip score question regarding ability to put on socks and tie a shoe correlated with the most individual planes of motion, but several WOMAC physical function questions also correlated with total and weighted range of motion calculations.

Enhancement of the value of hip questionnaires by telephone follow-up evaluation

Errors, omissions, false understanding, and contradictory answers can compromise the use of questionnaires to generate follow-up data. To assess the utility of and effort involved in adding routinely a telephone interview to clarify the questionnaire, a study of total hip arthroplasty patients was carried out. Thirty-six patients with 37 primary and 13 revision total hip arthroplasties filled out a standardized questionnaire (which asks a number of demographic questions as well as questions that allow calculation of the Medical Outcome Studies [MOS] 36-Item Short-form Health Survey [SF-36], Western Ontario MacMaster Arthritis Center [WOMAC] osteoarthritis index, and Harris hip score) prior to returning for routine follow-up evaluation a minimum of 1 year after surgery. Two hundred thirty-two of a possible 4,350 responses (5.3%) were missing, contradictory, or answered with two or more answers on the questionnaire. Only eight such defects occurred following the telephone interview by a skilled orthopaedic surgeon, representing a significant reduction in these defects (P < .005). The average time of the telephone call was 2.8 minutes (range, 1-12 minutes), and the average number of attempts to contact the patient was 1.4 (range, 1-6). All questionnaire data and questionnaire data plus telephone data were compared with data obtained from a subsequent face-to-face interview by a different skilled orthopaedic surgeon who was blinded to the data from both the questionnaire and the telephone interview. It is demonstrated that a telephone call to follow up a standardized, self-administered questionnaire is a very effective way to augment the quality and quantity of questionnaire responses.