This paper presents a methodology for measuring the femoro-pelvic joint angle based on in vivo magnetic resonance imaging (MRI) images taken under weight-bearing conditions. We assess the reproducibility of angle measurements acquired when the subject is asked to repeatedly assume a reference position and perform a voluntary movement.

We scanned a healthy subject in a lying position in a 3T MRI scanner to obtain high resolution (HR) images including two transverse T1-weighted TSE sequence scans at the pelvis and knee and a sagittal T1-weighted dual sense scan at the hip joint. We then scanned the same subject in a weight-bearing configuration in a 0.5T open MRI scanner to obtain related low resolution (LR) images of the femur and acetabulum. Four scan cycles were obtained with the subject being removed and reinserted between cycles in the Open MRI scanner. In each cycle, a block was inserted (up position) and removed (down position) under the subject's foot.

The femur and acetabulum bone models were manually segmented and the models from the LR (sitting) images were registered to the HR (supine) images. The femoroacetabular angles relative to the LR scanning plane for four cycles were calculated. The femoral angle relative to the scanner were quite repeatable (SD < 0.9°), the pelvic angles less so (SD ∼2.6–4.3°). The hip flexion angle ranged from 23°–34° in the down and up positions, respectively, so the block induced a mean angle change in the flexion direction of approximately 11° (SD = 1.7°).

We found that the femoral position could be accurately re-acquired upon repositioning, while the pelvic position was notably more variable. Limb position changes induced by inserting a block under the subject's foot were consistent (standard deviations in the relative attitude angles under 2°). Overall, our measurement method produces plausible measures of both the femoroacetabular angles and the changes induced by the block, and the reproducibility of relative joint changes is good.

ACKNOWLEDGMENTS: Dr. Kang was supported by the National Science and Engineering Research Council of Canada (NSERC) through a Postdoctoral Fellowship and conducted her research at the Centre for Hip Health and Mobility at Vancouver General Hospital, Canada.

Purpose

The undulating pattern of the distal femur is well recognized. Radiographs do not always represent the full extent of the undulations. With recent increasing use of guided growth technique in the distal femur, it is important to define safe zones for screw placement.

Purpose

Measurements of patellar kinematics are essential to investigate the link between anterior knee pain following knee arthroplasty and patellar maltracking. A major challenge in studying the patellofemoral (PF) joint postoperatively is that the patellar component is only partially visible in the sagittal and close-to-sagittal radiographs. The narrow angular distance between these radiographs makes the application of conventional bi-planar fluoroscopy impossible. In this study a methodology has been introduced and validated for accurate estimation of the 3D kinematics of the PF joint post-arthroplasty using a novel multi-planar fluoroscopy approach.

Purpose

Primary internal fixation of uncomplicated scaphoid fractures offers many advantages compared to conventional casting. However, ideal fixation placement along the central scaphoid axis can be challenging, especially if the procedure is performed percutaneously. Because of the lack of direct visualization, percutaneous procedures demand liberal use of imaging, thereby increasing exposure to harmful radiation.

It has been demonstrated that computer-assisted navigation can improve the accuracy of guidewire placement and reduce X-ray exposure in procedures such as hip fracture fixation. Adapting the conventional computer-assist paradigm, with preoperative imaging and intraoperative registration, to scaphoid fixation is not straightforward, and thus a novel tactic must be conceived.

Purpose

Introduce an Integrated Approach for Orthopedic-Sports Medicine Practice and Patient Care Management that

Is built around effective and efficient surgical techniques, and patient care management processes

Integrates Operations and Service Excellence best practices with patient care management processes

Integrates orthopedic care delivery between outpatient clinic, pre-surgery, surgery, inpatient, (acute care) and post acute care settings

Delivers exceptional clinical, patient satisfaction and financial outcomes as validated by independent national healthcare benchmarking organization

Helps position Ortho-Sports medicine services for strategic growth

Is replicable to develop Ortho-Sports Medicine Centers of Excellence

Presentation illustrates the ‘Ten Elements’ approach to implement the Ortho-Sports Medicine Centers of Excellence and demonstrate the effectiveness of the approach with an outcomes study from over 1000 total knee arthroplasty (TKA) procedures. During the presentation, the speakers would share the key clinical, patient satisfaction, and financial outcomes achieved by the implementation of the best practices defined in our ‘Ten Elements’ approach. All performance data elements are collected, validated and analyzed by an independent third party, national healthcare benchmarking company.

During the presentation Dr. Bramlett would elaborate on the surgical protocol, and the key differentiating steps in procedure technique from traditional approach that significantly enhances procedure effectiveness, efficiency and lowers the patient complication rate as demonstrated by benchmarking data. Speakers would further present the key elements of Total Knee Arthoplasty procedure that focus on patient education, patient participation in pre-surgical weight loss and pre-habilitation program, anesthesia approach, avoiding tourniquet use and deep veen thrombosis (DVT) risk reduction, early post operative patient ambulation and weight bearing, and post operative patient management approach. On average the ortho-sports medicine clinical of Alabama TKA patients are disharged from the hospital in 2.6 days, and experience 65 percent less complications than expected for a similar patient population and assume early control of their independent functionality.

Objectives

To study the vascularity and bone metabolism of the femoral head/neck following hip resurfacing arthroplasty, and to use these results to compare the posterior and the trochanteric-flip approaches.

Purpose: Patellar bracing is a common, mechanical-based treatment strategy for patellofemoral osteoarthritis (OA). It is thought that the brace corrects patellar tracking, however, this correction has not been quantified in the OA population. Through advances in magnetic resonance imaging (MRI), we can now assess patellar tracking in three-dimensions.

Method: We assessed three-dimensional patellar tracking in ten subjects with symptomatic radiographic patellofemoral knee OA using a validated, quasi-static, MRI-based method. Four conditions were studied:

no knee brace, no load,

Patellar tracking (flexion, spin and tilt; proximal, lateral and anterior translation) was assessed. Comparisons were made at 1° increments over the coincidental range of knee flexion between the no-brace and brace conditions, at no load and 15% BW load, using a paired t-test with Bonferroni correction.

Results: All subjects (7 female, 3 male, 60.9±1.3 yrs, 89.5±19.3 kg) had radiographic lateral patellofemoral OA and seven had concomitant tibiofemoral OA (KL grade≥2). Under no load, the brace extended (mean=2.7°, CI=[2.4°, 2.9°], P< 0.001) and medially tilted (mean=−1.4°, CI=[−1.6°, −1.2°], P< 0.001) the patellae and shifted them distally (mean=0.8mm, CI=[0.6mm, 0.9mm], P< 0.001), medially (mean=0.5mm, CI=[0.5mm, 0.6mm], P< 0.001) and posteriorly (mean=0.6mm, CI=[0.5mm, 0.6mm], P< 0.001). Under 15% BW load, the brace extended the patella (mean=2.4°, CI=[2.1°, 2.8°], P< 0.001) and shifted them distally (mean=1.3mm, CI=[1.1mm, 1.4mm], P< 0.001), medially (mean=0.8mm, CI=[0.7mm, 0.9mm], P< 0.001) and posteriorly (mean 0.6mm, CI=[0.5mm, 0.7mm], P< 0.001).

Conclusion: The brace extended the patellae for both loading conditions, suggesting that patellar flexion/extension is restricted by the brace. The brace tilted the patellae medially under no load only, suggesting when the quadriceps are active (15% BW load) the brace has little effect for tilt. While the effect of bracing on patellar tracking may appear small, the differences are of similar magnitude to those observed between normals and patients with patellofemoral pain, suggesting that braces may produce clinically significant changes in patellar tracking.

Purpose: Subchondral cortical and trabecular bone mineral density (BMD) may increase and/or decrease during different stages of osteoarthritis (OA) disease progression. 2D in-vivo imaging studies examining direct associations between increased proximal tibial BMD and knee OA offer conflicting results, which may be due to the inherent limitations of 2D BMD imaging tools. Our objective was to compare existing and novel 3D imaging techniques for distinguishing subchondral bone properties in OA and normal cadaveric tibiae.

Method: Eight intact cadaver knees from five donors (4M:1F; age: 77+/−10) were repositioned and scanned three times using QCT (0.5mm isotropic resolution, 0.15mSv dosage). BMD was assessed using

computed tomography absorptiometry (CT-OAM) which uses maximum intensity projections to assesses peak density values within subchondral bone, and

Average BMD at normalized depths of 0–2.5mm, 2.5–5.0mm, and 5.0–10mm from the surface were assessed using CT-TomasD. Regional analyses were performed consisting of:

medial/lateral (M/L) BMD ratio, and

Each bone was assessed for OA using a modified-KL scoring system: Normal (mKL=0); Early-OA (1–2); and Late-OA (3–4).

Results: OA was identified in four compartments of three tibiae (1 late OA+valgus, 1 late OA+varus, 1 early OA+neutral). Larger density differences between OA and normal knees were noted using CT-TOMASD compared with CT-OAM. CT-TomasD demonstrated that the two knees with late OA demonstrated M/L BMD ratios differing by more than 3.4 SD compared with normals, with peak cores higher than normals across all depths. The knee with early OA and neutral alignment demonstrated M/L ratios less than normals while core differences were highest proximally, with density becoming lower than normals with increasing depth.

Conclusion: CT-TomasD demonstrated larger differences between OA and normal subjects when compared with CT-OAM differences. This may be due to CT-OAM primarily assessing peak density within the thin subchondral cortical endplate; a region demonstrating fairly uniform peak densities within a limited range.

Purpose: Radiostereometric Analysis (RSA) is used to measure migration and inducible displacement (ID) of orthopedic implant devices to allow early prediction of implant failure (eg. Aseptic loosening). Total Ankle Arthroplasty (TAA) is used for the treatment of end-stage ankle arthritis. First generation TAA implant have meet with widespread failures while some second generation TAA implants are showing improved results. In this study RSA is used to evaluate the biomechanical properties of a new third generation TAA implant in an attempt to set a standard for the biomechanical evaluation on TAA implants in-vivo.

Method: Patients undergoing TAA were enrolled consecutively (n=12; 7 males; mean age=59 years; mean BMI=29) and had 8 markers (0.08mm) inserted in both the tibia and talus during surgery. Standing, weight-bearing RSA exams were performed at 3 and 6 months and compared to concurrent supine exams to determine component ID.

Results: For tibial components: at six months the components had translated posteriorly (0.3mm±0.5) and proximally (0.5mm±0.2), tilted into varus (0.5°±1.3), and tilted posteriorly (0.4°±0.8). The magnitudes of ID for the tibial components were moderate (mean < 0.2mm and 0.5°, standard deviation < 0.3mm and 2.2° in each direction). For talar components: at six months the components had translated distally (0.28mm±0.35), rotated internally (0.21°±1.32) and tilted posteriorly (0.15°±0.90). There was varus/valgus tilt measured in the talar components but there was no consistent direction of migration (0.03°±1.4). At six months the magnitudes of ID for the talar components were small (mean < 0.1mm and 0.25°, standard deviation < 0.2mm and 0.6° in each direction).

Conclusion: An RSA methodology has been established to predict stability.

Our aim was to determine the effect of the initial pattern of fracture and the displacement of fragments on the outcome of proximal humeral fractures treated conservatively. We followed 93 consecutive patients prospectively for one year. Final movement and strength were compared with those of the contralateral side. The final American Shoulder and Elbow Society score and the Disabilities of Arm, Shoulder and Hand and Short-Form 36 questionnaires were compared with those provided by the patient on the day of the injury. Radiographs and CT scans with three-dimensional reconstruction were obtained in all patients. The pattern of the fracture and the displacement of individual fragments were analysed and correlated with the final outcome. There were two cases of nonunion and six of avascular necrosis. The majority of the fractures (84 patients; 90%) followed one of the following four patterns: posteromedial (varus) impaction in 50 patients (54%), lateral (valgus) impaction in 13 (14%), isolated greater tuberosity in 15 (16%), and anteromedial impaction fracture in six (6%). Head orientation, impaction of the surgical neck and displacement of the tuberosity correlated strongly with the outcome.

In fractures with posteromedial impaction, a poor outcome was noted as the articular surface displaced inferiorly increasing its distance from the acromion. A poorer outcome was noted as a fractured greater tuberosity displaced medially overlapping with the posterior articular surface. Lateral impaction fractures had a worse outcome than other patterns of fracture.

Recently, gender-specific designs of total knee replacement have been developed to accommodate anatomical differences between males and females. We examined a group of male and female distal femora matched for age and height, to determine if there was a difference in the aspect ratio (mediolateral distance versus anteroposterior distance) and the height of the anterior flange between the genders. The Hamann-Todd Collection provided 1207 skeletally mature cadaver femora. The femoral length, the anteroposterior height, height of the lateral and medial flanges and the mediolateral width were measured in all the specimens. The mechanical axis of the femur, the cut articular width and the aspect ratio were assessed. Statistical analysis of the effect of gender upon the aspect ratio and the lateral and medial flanges was undertaken, controlling for age, height and race.

The mean aspect ratio of male femora was 1.21 (sd 0.07) and of female femora it was 1.16 (sd 0.06) (p < 0.001). There was no significant difference between male and female specimens in the mean size of the lateral flange (6.57 mm (sd 2.57) and 7.02 mm (sd 2.36), respectively; p = 0.099) or of the medial flange (3.03 mm (sd 2.47) and 3.56 mm (sd 2.32), respectively; p = 0.67). Future work in the design of knee prostheses should take into account the overall variability of the anatomy of the distal femur.

Background: Diagnosis and treatment of cancer are highly stressful for patients. Everyday life is disrupted for the vast majority of patients and their relatives and the cancer experience often results in physical, psychological, social, practical, and spiritual concerns.25% to 40% of cancer survivors continue to suffer from distress.

Goal: To improve the referral to specific professionals.

Intervention: Implementation of the distress thermometer: for the future demand on healthcare, a National Cancer Control Program was developed. Two objectives are the availability and introduction of a validated screening instrument capable of indicating the need for specialized psychosocial assistance and the inclusion of screening for psychosocial problems in the national guidelines for oncologic care. These 2 objectives are in line with the American National Comprehensive Cancer Network (NCCN) practice guideline of distress management. This program introduced the Distress Thermometer (DT), an easily understood, self-reported measure of distress. Patients are asked to rate their overall distress on a visual analogue scale (a thermometer) from 0 (no distress) to 10 (extreme distress).

Implementation: Baseline measurements were done in 2008. In January 2009 we started using the distress thermometer at the orthopedic oncology outpatient clinic. The first results of the baseline measurements and the implementation so far will be presented during the EMSOS 2009.

A longer stay in the hospital after primary total hip replacement is consistent with an increased morbidity and slower recovery for patients. In addition, it is among the more costly aspects of a total joint replacement. A process, which reduces the length of stay following this procedure and synchronically maintains the high standards of safe care would certainly improve the clinical practice and provide financial benefits.

Our objective was to evaluate the efficiency of a holistic perioperative, accelerated recovery programme following this procedure and in particular to assess its impact in the shot term patient’s recovery, morbidity, complications, readmission rate and cost savings for the NHS.

Eighty-nine patients participated in our rapid recovery programme, which is a comprehensive approach to patient care, combining individual pre-operative patient education, pain management, infection control, continuous nursing and medical staff motivation as well as intensive physiotherapy in the ward and the community. Forty-eight male and 41 female patients with an average age of 69 (range-50 to 87) underwent a total hip replacement in an NHS District General Hospital. The average BMI was 28 (range-18 to 39) and the average ASA 2.3 (range-1 to 4). The procedure was performed by 3 different surgeons using the same operative standards. A standardised post-operative protocol was followed and the patients were discharged when they were medically fit and had achieved the ward physiotherapy requirements. They were then daily followed up by a community orthopaedic rehabilitation team in patient’s own environment as long as it was required.

The average length of stay was reduced from 7.8 days to 5. There was no increase in complications–or readmissions rate while there were significant cost savings. The waiting list for this surgery was reduced and the patient’s satisfaction was high.

The rapid recovery programme for primary total hip replacement surgeries has been proved to be an efficient method of reducing the length of stay in hospital and consequently the financial costs while it ensures the safe and effective peri-operative management of patients.

Introduction: Geometry of the proximal femur has been identified as a risk factors for hip fracture. It is also suggested that the geometry of the proximal femur can influence the fracture type.

Aims: To identify if proximal geometry and hip fractures are related in two different population groups. Scotland–Monklands General Hospital, Lanarkshire–and Australia -Flinders Medical Centre, Adelaide.

Methods: Retrospective comparison of length and width of the femoral necks in 200 hip fracture patients. 100 patients in the Australian group and 100 patients in the Scottish group were analysed. 50 intracapsular and 50 intertrochanteric fractures were included in each group. All measurements where made from standardised digital anteroposterior radiographs. We attempted to correlate the length and width of the femoral neck with the fracture type.

Results: The populations were matched for age and sex, with the majority of fractures sustained by women. The results for the both populations show that a patient sustaining an intracapsular fracture is more likely to have a longer femoral neck (mean 40.56mm; Scottish population, 39mm; Australian population) than one sustaining an intertrochanteric fracture (mean 31.70mm; Scottish population, 29mm; Australian population) [P < 0.0001]. The femoral neck was also narrower in the intracapsular group. This was significant in Scottish population (mean 38.56mm, P < 0.03), but not in the Australian population (mean 38.3mm, P = 0.067). We also found that men had longer, wider femoral necks (P < 0.0001) compared to the female group.

Discussion: We found that hip fracture pattern is linked to proximal femoral geometry. This relationship is statistically significant in both population groups. Anthropologically, as the human race evolves and people get taller, their femoral neck lengths are increasing. This could translate into a change in the number and type of hip fractures. Intracapsular fractures may predominate and this could have implications on both treatment outcomes and resources for hip fracture patients.

Purpose: To evaluate the functional outcome of operatively treated Lisfranc injuries.

Method: Over a 7-year interval from 1998 to 2005, 184 skeletally mature patients were identified retrospectively with operatively treated Lisfranc injuries. 85 patients had prospectively measured SMFA functional outcomes and satisfaction surveys. The gender was 37 males and 48 females. Mean age was 39 years (range 17–93).

Results: The mechanism was fall (31), MVA (24), crush (15), equestrian (5), or twisting (10). Patients were operatively treated with open reduction internal fixation (ORIF, 53) or primary arthrodesis (PA, 32). The SMFA reliability for this patient sample was 0.892. The function and bother outcomes were 19.4 and 15.8, respectively. The function (21.5 vs. 16.0, p=.11) and bother (17.5 vs. 13.0, p=.25) outcomes were not significantly different for ORIF vs. PA, respectively. In the ORIF group, HW removal (40 of 53) performed better than HW retention (13 of 53) with outcome bother but not function measures of (14.7 vs. 26.1, p< 0.05).

Conclusion: If performed well, either ORIF or PA technique function well. Patients are more satisfied with the results and appearance of PA over ORIF. HW removal compared to HW retention positively affect bother not function measures. Secondary surgeries negatively affect both bother and function measures. Patients with pain, associated foot or polytrauma injuries function worse.

Whole blood metal ion levels remain a concern in those patients undergoing total hip replacement with metal bearing surfaces. The determination of baseline reference levels are essential if useful information can be gleaned from in vivo studies of functioning implants. We set out to prospectively determine chromium and cobalt metal ion concentrations in patients undergoing total hip replacement to determine reference levels of these metal ions.

100 patients with normal renal function, no occupational or environmental exposure to cobalt and chromium, and an absence of implanted metals were recruited into the study. Metal ion levels were determined using two different assay methods. Both ICP-MS (Inductively Coupled Plasma Mass Spectroscopy) and GFAAS (Graphite Furnace Atomic Adsorption Spectroscopy) are well recognized analytical techniques for the quantification of trace elements. Levels were correlated with gender, age and place of residence.

There was considerable variability in whole blood metal ion levels, with the ICPMS being more sensitive and consistent than the GFAAS method. Direct comparison of concentration levels determined by the two methods revealed no significant correlation. There was no correlation with age, gender and place of residence

Our findings would favour the use of the ICP-MS to determine reference levels and as a baseline for metal ion surveillance pre-operatively in patients undergoing metal-on-metal total hip replacements. We also determined that changes in whole blood metal ion levels are more significant than actual levels in patients who have undergone total hip replacement.

Purpose: Osteoarthritis (OA) is the most common form of arthritis in the United States and according to the National Institutes of Health, affects over 21 million people. This degenerative joint disease has repeatedly been linked to obesity. It is hypothesized that obesity, defined as a body mass index (BMI) over 30 kg/m2, increases the incidence of OA through increased joint pressure and disruption of normal metabolism. The actual changes in metabolism resulting from obesity and possibly preceding OA have not been thoroughly investigated. The purpose of this study was to identify the relationship between chondrocyte metabolism and BMI in osteoarthritic tissue.

Method: Grade 0 or 1 cartilage was removed from the medial and/or lateral femoral condyles after total knee arthroplasty. Isolated chondrocytes were then resus-pended in alginate beads at 2×106 cells/mL. The beads were equilibrated in media containing 10% fetal bovine serum for 7 days (37°C) and then separated into wells (8 beads/well) with 1 mL media. Media was replaced every 48 hours. At day 5, 9, and 13 days, glycosamino-glycan (GAG) content was measured in the cell pellet, alginate, and saved media using the dimethylmethylene blue (DMMB) assay. The DMMB results were normalized to DNA content. All procedures were approved by the University of Wisconsin – Madison, Institutional Review Board.

Results: At day 5, the average normalized GAGs from the obese group (BMI > 30 kg/m2) was > 4-fold higher than the average normalized GAGs in the non-obese group (BMI < 30 kg/m2). The 4-fold difference in normalized GAGs continued at day 9 with significance (p=0.0087) and widened at day 13, without significance. Some osteoarthritic knees had less tissue quality, therefore GAG testing was limited to earlier study days resulting in variable sample numbers for each study day.

Conclusion: The study results reveal a significant relationship between normalized GAGs and BMI in this population of osteoarthritic patients, supporting the connection between osteoarthritis and obesity previously reported. Higher patient BMI (> 30 kg/m2) may be similar to dynamic compression injuries that cause increased GAG synthesis in response to cartilage damage. In conclusion, elevated normalized GAGs in obese patients’ chondrocytes suggests increased cartilage damage.

Purpose: Femoral neck fracture collapse and shortening has been a desired effect of parallel screw fixation to promote healing. While some degree of compression might be beneficial, it remains unknown whether the effects of uncontrolled femoral neck shortening leads to detectable functional impairment. We aimed to evaluate the effect of shortening and varus collapse after cancellous screw fixation of femoral neck fractures on patient functional status and quality of life.

Method: The databases of four University Hospitals were screened to identify patients with a healed isolated femoral neck fracture. Patients were contacted by telephone to complete Short-form 36(SF36) and Euroquol-5D(EQ5D) questionnaires (Primary outcome: SF36 physical functioning score[PF]). Femoral neck shortening and varus collapse were assessed by three independent reviewers blinded to functional outcome results based on the latest follow-up radiographs and categorized into three grades: None/Mild (within 5mm/5°), Moderate (5–10mm/5–10°), and Severe (> 10mm/> 10°). The minimal clinically important difference for SF36 PF score equals 12 points (1/2 of Standard deviation).

Results: Out of 660 patients screened at all four sites 70 met the inclusion criteria and were available for follow-up. The average follow-up was 20 months and an the average age was 71 years. Overall, there were 24/70 patients with none/mild femoral neck shortening, 25/70 with moderate shortening and 21/70 with severe shortening. Patients with severe shortening of their hip had significantly lower SF36 physical functioning scores (No/Mild vs. Severe shortening: 74 vs. 42 points, p=0.01). Similar important effects occurred with moderate shortening suggesting a gradient effect (No/Mild vs. Moderate shortening: 74 vs. 53 points). Some degree of varus collapse occurred in 39% of the patients and correlated moderately with the occurrence of shortening (r=0.66, p< 0.001).

Conclusion: A large proportion of displaced and undisplaced femoral neck fractures fixed with cancellous screws heal in a shortened position (66%) and varus (39%). The differences in function we observed represent patient important declines and suggest that uncontrolled sliding with cancellous screw fixation has limitations.

In an osteological collection of 3100 specimens, 70 were found with unilateral clavicular fractures which were matched with 70 randomly selected normal specimens. This formed the basis of a study of the incidence of arthritis of the acromioclavicular joint and the effect of clavicular fracture on the development of arthritis in the ipsilateral acromioclavicular joint. This was graded visually on a severity scale of 0 to 3. The incidence of moderate to severe arthritis of the acromioclavicular joint in normal specimens was 77% (100 specimens). In those with a clavicular fracture, 66 of 70 (94%) had arthritis of the acromioclavicular joint, compared to 63 of 70 (90%) on the non-injured contralateral side (p = 0.35).

Clavicles with shortening of 15 mm or less had no difference in the incidence of arthritis compared to those with shortening greater than 15 mm (p = 0.25). The location of the fracture had no effect on the development of arthritis.

INTRODUCTION. The grip test is usually included in common protocols of functional evaluation. Till today a dynamometer Jamar was used to evaluate Maximum Isometric Strength. At this moment we use isokinetic dynamometers to analyse grip strength in isokinetic way. As a few bibliographic references for this valuation techniques we have designed an study at healthy population to obtain the normal values of grip strength and the influence of individual factors, like sex, age and side-dominance.

MATERIAL AND METHODS. A 321 healthy hands serial was included. The average age was 37.2 years old (ranged 17–63). Mostly of them were men (211 cases, 65.7%). 150 are side-dominant cases (46.7%). All of them has been valuated by Dexter Hand Evaluation. Two speeds 30°/s and 60°/s was used in the study. And the extent used was 4.3 cm. Five trials was done in each velocity. We acquired Maximum Isokinetic Strength and Work.

RESULTS. The values were for strength (Kg) 38.4 at 30°/s and 35.0 at 60°/s and for work (Kg-cm) 98.5 at 30°/s and 86.7 at 60°/s. The side-dominant hand are stronger than non-dominant ones (10.3% in 30°/s, p< 0.001; 11.9% in 60°/s, p< 0.001). Women had less strength than men (37% in both speeds, p< 0.001). The age has less important as isokinetic strength values are more or less the same till 39 years old. After that there is a slow drop of the strength in aged cases.

At last we show tables of normal values at healthy population. The influence of sex and side-dominant are shown as a percentile distribution.

CONCLUSIONS. The isokinetic strength evaluation of hand grip is a very value method in the functional evaluation of the hand. This study gives normal values in healthy hands and the influence of sex, age and side-dominance.