Biomedical subjects

Mark D Rossi

Publications and source records attributed to Mark D Rossi.

8 recordsLinked to original sources

PubMed2007

Neurovascular injuries in acetabular reconstruction cage surgery: an anatomical study.

Acetabular reconstruction cages are indicated for severe combined segmental and cavitary acetabular bone defects. The purpose of this study was to evaluate the implications of screw placement and drill plunge and the potential insult to anatomical structures when implanting acetabular reconstruction cages. A segmental cavitary defect was reamed into the acetabulum and a cage was implanted in each of the 10 hemipelvises. The relative course of the superior gluteal neurovascular bundle was mapped to assess dissection intervals. When cage screws were placed at least 15 mm longer than needed, 13% and 20% of screws of the superior flange and anterior rim hit the femoral nerve, respectively, and approximately 60% of the screws placed in the posterior rim endangered the obturator nerve. A "safe zone" for screw size may be a 15- and 25-mm screw for the superior flange and posterior rim, respectively.

Acetabulum↗

PubMed2006

Mobility and perceived function after total knee arthroplasty.

Mobility using the timed up and go (TUG) and perceived pain, stiffness, and physical function (Western Ontario McMaster Universities Osteoarthritis Index) were documented after total knee arthroplasty (TKA). The relationships between mobility and perceived function are limited post-TKA. The first purpose of this study was to determine and compare the TUG test between individuals (n = 11) post-TKA and age-sex-related controls (n = 11). The second purpose of this study was to explore the relationships between mobility and self-reported function post-TKA. The TKA group was 28% (P < .05) slower in completing the TUG compared with controls and reported difficulty in attempting challenging tasks. The TUG was moderately related to the physical function (0.63) dimension of the Western Ontario and McMaster Universities Osteoarthritis Index, as well as the aggregate Western Ontario and McMaster Universities Osteoarthritis Index score (0.59).

Activities of Daily Living↗

PubMed2006

Postdischarge costs in arthroplasty surgery.

Postdischarge costs associated with primary arthroplasty surgeries have received limited attention in the literature. Our objective was to identify the costs incurred after discharge in primary arthroplasty and to estimate annual postdischarge expenditures in the United States. A cohort of 136 patients who underwent primary arthroplasty was studied. Comprehensive rehabilitation unit (CRU) and home care (HC) costs were obtained. The National Hospital Discharge Survey 2003 data were used to model the national discharge cost estimates. Local patient-oriented outcome was also compared in the patients discharged to CRU vs HC. Total costs were significantly lower in patients discharged directly to home vs those sent to the CRU and who subsequently received HC ($2405 vs $13435, P < .001); both patient groups experienced similar quality of life improvements. An estimated $3.2 billion is spent annually on postsurgical rehabilitation after arthroplasty. Postdischarge costs are significantly higher for patients going to a CRU vs those discharged home; yet, both groups had comparable short-term outcomes.

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PubMed2006

Knee extensor and flexor torque characteristics before and after unilateral total knee arthroplasty.

OBJECTIVE: The purpose of this study was to document torque characteristics and strength recovery of the knee extensors and flexors before and up to 1 yr after unilateral total knee arthroplasty. Our goal was to also document the responsiveness of isokinetic testing over repeated measures. DESIGN: Thirteen individuals voluntarily participated in this study. Torque production of the knee extensors and flexors was assessed isokinetically at 1.047 and 3.142 radians/sec. RESULTS: Regardless of time, the knee extensors and flexors on the involved side generated a range of 76 and 82% of the average peak torque produced by the uninvolved side at both 1.047 and 3.142 radians/sec, respectively. At 30 days after surgery, there was a "dip" in both knee extensor and flexor torque production. Responsiveness indices for the knee extensors and flexors ranged from 0.95 to 2.12 at 1.047 radians/sec. At 3.142 radians/sec, the responsiveness indices for the knee extensors and flexors ranged from 0.65 to 2.87. CONCLUSION: One year after surgery, there continues to be knee extensor and flexor strength asymmetry between limbs. Moreover, within the first month after surgery, the knee extensors and flexors are at the weakest point compared with before, 60 days, and 1 yr after surgery. Isokinetic testing is a useful tool to document torque production before and in the early time after unilateral total knee arthroplasty.

Aged↗

PubMed2006

Assessment of hip extensor and flexor strength two months after unilateral total hip arthroplasty.

This investigation assessed strength of the hip extensors and flexors when assistive devices and weight bearing are changing after total hip arthroplasty (THA). Eleven individuals (6 men, 5 women; mean age 74.45 +/- 4.88 years) with unilateral THA were evaluated isokinetically at 60 degrees x sec(-1) before surgery on the involved and uninvolved limbs. Each subject's involved limb was tested 60 days after surgery. Comparisons were made between involved and uninvolved limbs and between the involved limb before surgery and 60 days after surgery for both the hip extensors and flexors. Hip extensor and flexor strength before surgery on the involved side was 39% and 29% lower, respectively, compared with the uninvolved side. Sixty days after surgery, strength of the hip extensors and flexors improved 50% and 27%, respectively, compared with before surgery. Over the 60-day interval, the responsiveness of isokinetic testing was high for both muscle groups (range, 0.74-1.51). It would seem appropriate that intensive rehabilitation continue through at least the 60-day period and that isokinetic testing is an effective tool to monitor hip strength before and after surgery.

Aged↗

PubMed2005

Early strength response of the knee extensors during eight weeks of resistive training after unilateral total knee arthroplasty.

The purpose of this study was to document the early history of knee extensor torque production before and after total knee arthroplasty (TKA), explore the relationship between strength assessments, and describe an 8-week resistive-training protocol. Thirty-eight individuals (19 men, 19 women) with unilateral TKA volunteered to participate in this repeated-measures study. For this group, the mean age was 72.23 +/- 5.34 years; height was 168.00 +/- 8.57 cm; and weight was 79.42 +/- 14.57 kg. Torque production of the knee extensors was assessed isokinetically at 60 and 180 degrees .s(-1) before surgery, 30 days after unilateral TKA (+30), and 60 days after unilateral TKA (+60). Torque production was significantly different between limbs at both 60 and 180 degrees .s(-1) (p < 0.0125) before surgery. Torque production was lower at +30 compared with before surgery at both 60 and 180 degrees .s(-1) (p < 0.002). By +60, torque production was greater than at +30 at both 60 and 180 degrees .s(-1) (p < 0.002).

Aged↗

PubMed2004

Lower-limb force production in individuals after unilateral total knee arthroplasty.

OBJECTIVE: To determine and compare lower-limb force production during a single-leg horizontal press in involved and uninvolved limbs in people with unilateral total knee arthroplasty (TKA) and the limb of age- and gender-matched subjects. DESIGN: Quasi-experimental, posttest only control group design. SETTING: Subjects living in the community and were tested at a university facility. PARTICIPANTS: Nine people with unilateral TKA and 9 subjects without TKA volunteered. The mean postsurgery time for the TKA group was 15.89+/-6.62 months. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Force production in kilograms during a single-leg press. RESULTS: Lower-limb force production differed significantly between involved and uninvolved limbs (P=.007) for the unilateral TKA group. Lower-limb force production of the involved limb in persons with unilateral TKA was significantly lower than the limb of the age- and gender-matched controls (P=.0001). CONCLUSIONS: Lower-limb force production on the involved side was significantly lower than the uninvolved side. When compared with an age-matched control group, subjects with unilateral TKA produced less force during a single-leg horizontal press.

Activities of Daily Living↗

PubMed2002

Comparison of knee extensor strength between limbs in individuals with bilateral total knee replacement.

OBJECTIVES: To determine and compare force production of the knee extensors between limbs after bilateral total knee arthroplasty (TKA). DESIGN: Two repeated-measures designs (2 factors: limb, time) assessing for differences in strength between limbs over 3 times at 2 different testing speeds. SETTING: Private and institutional practice. PARTICIPANTS: Fourteen volunteers (6 men, 8 women; mean age +/- standard deviation, 74.57 +/- 5.5 y; height, 169.91 +/- 9.43 cm; weight, 76.42 +/- 9.85 kg) with bilateral TKA. Open-chain knee extensor strength was measured in both legs before surgery and 30 and 60 days after TKA at 60 degrees /s and 180 degrees /s. INTERVENTION: Rehabilitation 3 times weekly for 8 weeks. Treatment consisted of gait, transfer training, stationary cycle work, and a progressive resistance-training program. MAIN OUTCOME MEASURE: Peak torque measured isokinetically. RESULTS: Limb by time interaction was not significant for either 60 degrees /s (F(2,26) =.75, P =.351) or 180 degrees /s (F(2,26) =.78, P =.393). A significant main effect of time was found at 60 degrees /s (F(2,26) = 14.22, P =.0001) and 180 degrees /s (F(2,26) = 10.47, P =.003). CONCLUSIONS: During the first month after TKA, bilateral knee extensor force-production decreased significantly compared with preoperative force production.

Aged↗