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Glenohumeral anatomic study: a comparison of male and female shoulders with similar average age and BMI.

Numerous anatomic studies of the shoulder have previously quantified the size, shape, and variability of either the humerus (1-7) or scapula (2,4,7-17) individually, and some have assessed the variability as a function of gender. (6,7,11,14,15) However, few studies (4,7) have attempted to quantify the relationship of the humerus to the scapula to better understand the spatial variation of these bones in both male and female shoulders. An improved understanding of the variability in this spatial relationship may have many applications related to shoulder arthroplasty prosthesis design, computer navigation, and surgical implantation techniques (as many complications associated with shoulder arthroplasty involve patient-specific factors). Additional considerations should be given to gender effects since the majority of shoulder arthroplasty is performed in females, with females being recipients for reverse shoulder arthroplasty (rTSA) approximately 65% of the time. To that end, we conducted an anatomic study on 74 3D CT reconstructions of the shoulder (37 males and 37 females) to quantify the morphology of the humerus, scapula, and the spatial relationship between the two to better understand the role of gender on the anatomic variability of the glenohumeral joint.

Materials and Methods

Seventy-four cadaveric shoulder CT scans, 37 males (76.7 [+ or -] 8.8 years; BMI = 23.7 [+ or -] 6.3) and 37 females (78.1 [+ or -] 10.9 years; BMI = 21.3 [+ or -] 5.8) were reconstructed using Mimics[R] (Materialise NV, Leuven, Belgium) to create 3D models of the humerus and scapula. CTs were taken with 0.5 mm slice thickness. After 3D reconstruction, each CT bone model was analyzed in Rapidform[R] (3D Systems) to quantify variations in morphology between males and females with statistically equivalent age (p = 0.59) and BMI (p = 0.09). Differences in morphology between males and females were also compared relative to each humeral head diameter in order to normalize the parameters for size. Measurement reproducibility was determined to be [+ or -] 1.0 mm for linear parameters and [+ or -] 1.0[degrees] for angular parameters. A Student's two-tailed, unpaired t-test was used to identify differences between male and female measurements for the glenohumeral joint relation ships, the humeral morphology, and the scapula and glenoid morphology, where p < 0.05 denoted a significant difference. Linear correlations were also performed between all joint measurements.

To quantify the spatial glenohumeral joint relationships, each reconstructed CT bone model was oriented with the humerus in 10[degrees] of abduction in the scapular plane and positioned to permit 3 mm space between the humeral head and glenoid to account for the thickness of the cartilage and labrum (Fig. 1). As described in Figure 2 and Table 1, 16 measurements were obtained to quantify the position of the humerus relative to the scapula in the scapular plane. These scapular plane spatial measurements were selected because they can be visualized and measured from anterior-posterior (AP) radiographs and therefore may be viable as preoperative planning parameters. The coefficient of variation of each measurement was quantified to assess the viability of each measurement to be taken from AP radiographs.

As described in Figures 3, 4, and 5, and Table 2, 24 measurements were obtained to quantify the morphology of the humerus independent of the scapula. The humeral shaft outer diameter (OD) and humeral intramedullary (IM) canal diameter were measured using a best fit circle at four different heights (75 mm, 150 mm, and 225 mm from the humeral head and also at the deltoid tuberosity). The linear offset between these best fit circles was also quantified but not depicted in the figures. The humeral head diameter was measured with a best fit sphere; the humeral head thickness was measured from a plane defining the anatomic neck, and the articular surface area was calculated using this sphere diameter and associated thickness. The medial, posterior, and total offset of the humeral head center were measured relative to the IM axis; the anterior and posterior distances from the humeral head center were also measured for the lesser and greater tuberosities, respectively. The humeral head neck angle was measured relative to the IM axis, and the humeral head retroversion was measured relative to the epicondylar axis.

As described in Figures 6 through 9 and Table 3, 22 measurements were obtained to quantify the morphology of the scapula and glenoid independent of the humerus. Glenoid height was measured linearly along the superior-inferior (SI) glenoid axis. Glenoid width was measured linearly at the upper third and lower third of the glenoid as a line perpendicular to that SI glenoid axis; ratios between glenoid height and width were also calculated. The glenoid articular surface area was measured digitally from the selected glenoid face. Glenoid articular curvature was measured with a best-fit sphere to the selected glenoid face. Glenoid neck length was measured linearly along the scapular plane between the inferior glenoid rim and the infraglenoid tubercule. Scapular neck angle was measured as the angular difference between the scapular neck and the SI glenoid axis. Glenoid version was measured as the angular difference between the anteriorposterior (AP) glenoid axis and the long axis of the scapula (defined by the line connecting the center of the glenoid and the intersection of the scapular spine and scapular body at the medial border); greater than 90[degrees] indicates retroversion. Similarly, glenoid inclination was measured as the angle between the long axis of the scapula and the SI glenoid axis; greater than 90[degrees] indicates inclination. Acromion length was measured linearly along the lateral border between its most anterior and posterior points. Acromion thickness was measured at two different locations: 1. SI width in the middle of the lateral border and 2. AP width at its intersection with the scapular spine. The posterior-superior (PS) acromionglenoid distance was measured linearly in the AP direction between the most anterior point of the lateral border and the SI glenoid axis. The posterior-inferior (PI) acromion-glenoid distance was measured linearly in the AP direction between the most posterior point of the lateral border and SI glenoid axis. The lateral acromion-glenoid distance was measured linearly in the medial-lateral (ML) direction between the most lateral point of the lateral boarder and the center of the glenoid. The acromial-glenoid angle was measured as the angular difference between the lateral border and the SI glenoid axis. The coracoid tip-glenoid distance was measured linearly in the ML direction between the most lateral point of the coracoid to the center of the glenoid. Finally, the coracoid base-glenoid distance was measured linearly in the ML direction between the most lateral aspect of the coracoid base to the center of the glenoid.

Results

As described in Table 1, spatial glenohumeral relationships of male shoulders were significantly larger than that of female shoulders in 13 of 16 measurements. However, when each of the 16 glenohumeral relationship measurements were normalized by the humeral head diameter, only glenohumeral dimensions 8 and 10 were observed to be significantly different between male and female shoulders (with dimension 8 for male shoulders being significantly larger than female shoulders, and dimension 10 for female shoulders being significantly larger than male shoulders). These normalized measurements suggest that coracoid morphology is highly variable according to gender. Additionally, measurements 1 to 3, 9, 10, 13, 15, and 16 were all found to have coefficients of variations (COV) less than 15%, with dimensions 1, 2, and 16 having a COV between 6% and 8% for both male and female shoulders, suggesting that these scapular plane measurements are reliable and can be measured on AP radiographs.

As described in Table 2, measurements of male humeri were significantly larger than that of female humeri in 17 of 24 measurements. Male humeri were associated with significantly larger and thicker humeral heads that were more offset (particularly in the posterior direction) than female humeri. Additionally, male humeri were associated with significantly more anterior shift of the lesser tuberosity and significantly more posterior shift of the greater tuberosity. The male humeri were also observed to be significantly longer, with larger OD and IM diameters at all four resection heights. However, when each measurement was normalized by the humeral head diameter, only humeral dimensions 8, 11 to 14, 16, 18, and humeral head articular surface area were observed to be significantly larger for male humeri than female humeri. When comparing the normalized measurements, humeral dimensions 3, 4, 10, and 19 were observed to be significantly larger for female humeri than male humeri.

As described in Table 3, scapula and glenoid measurements for male shoulders were significantly larger than that of female shoulders in 11 of 22 measurements. Male scapula were associated with significantly larger and wider glenoids than female scapula, with male glenoids having significantly larger articular surface areas. Additionally, male acromions were observed to be significantly thicker (both SI and AP) and longer than female acromions, with male acromions having significantly larger PI acromion-glenoid distances and lateral acromion-glenoid distances. Finally, male coracoids were observed to be longer than females, with males having longer coracoid tip-glenoid distances. However, when each measurement was normalized by the humeral head diameter, only scapula and glenoid dimensions 9, 11, and the glenoid articular surface area were observed to be significantly larger for male scapula than female scapula. When comparing the normalized measurements, scapula and glenoid dimensions 5, 6, 16, 18, 19, and both glenoid height and width ratios were observed to be significantly larger for female scapula than male scapula.

Considering only linear correlations greater than 0.9 between the direct (non-normalized) measurements, both males (r = 0.99) and females (r = 0.99) had a positive correlation between humeral head diameter (humeral dimension #1) and humeral head articular surface area. Additionally, both males (r = 0.97) and females (r = 0.95) had a positive correlation between humeral head medial offset (humeral dimension #5) and total humeral head offset (humeral dimension #7). Both males (r = 0.95) and females (r = 0.92) also had a positive correlation between the humeral intramedullary canal diameter at the location of the deltoid tuberosity (humeral dimension #13) and the humeral intramedullary canal diameter at a location of 150 mm inferior to the top of the humeral head (humeral dimension #15). Males were only observed (r = 0.91) to have a positive correlation between the lateral acromion and top of the greater tuberosity (glenohumeral joint relationship #4) and the lateral acromion and lateral greater tuberosity (glenohumeral joint relationship #6). Grouping male and female shoulders together demonstrated additional positive linear correlations greater than 0.9 between humeral dimensions #12 and #14 (r = .90), humeral dimensions #12 and #16 (r = 0.91), humeral dimensions #14 and #16 (r = 0.95), humeral dimensions #14 and #18 (r = 0.90), humeral dimensions #16 and #18 (r = 0.91), and finally scapular dimensions #8 and the glenoid articular surface area (r = 0.92).

Discussion

The results of this study demonstrate numerous gender differences in scapular plane glenohumeral joint spatial relationships, humeral morphology, and scapula and glenoid morphology. While many anatomic studies of the glenohumeral joint have been conducted previously, (1-21) the majority only quantify the morphology of one aspect, the humerus or the scapula or they evaluate both sides of the joint independently without quantifying the spatial relationships across the joint--particularly with respect to gender. One of the strengths of this study is that anatomic measurements were assessed on an equal number of male and female specimens, with each group having a statistically equivalent age and BMI.

These anatomic study results demonstrate that humeral morphology is highly variable with male humeri being significantly larger than female humeri in approximately two-thirds of the measurements. As described in Table 4, the means and standard deviations observed with our proximal humeral measurements are similar to that of previously published anatomical studies (1,3-7) of the humerus. These results also demonstrate that scapula morphology is highly variable with male scapula being significantly larger than female scapula in approximately one half of the measurements. As described in Table 5, the means and standard deviations observed with our glenoid, acromion, and coracoid measurements are similar to that of previously published anatomical studies (4,9-11,13-17,22) of the scapula. These comparisons both validate our results but also demonstrate (relative to Tables 2 and 3) that mean results by themselves can be misleading as numerous anatomic parameters of the humerus and scapula were observed to be binomial (due to gender). Two notable anatomic studies (4,7) have previously quantified a few of these measurements across the joint. Both Iannotti and coworkers (4) and Takase and associates (7) reported on the lateral humeral offset (e.g., glenohumeral joint relationship # 1). Iannotti and coworkers reported an average of 56 [+ or -] 5.7 mm, whereas Takase and associates reported an average of 62.3 mm [+ or -] 6.2 mm. Our results were nearly identical in magnitude and variability with that of Iannotti and coworkers. Additionally, our results on the glenohumeral offset (e.g., glenohumeral joint relationship # 2) were nearly identical in magnitude and variability to that of Takase and associates (55.7 mm [+ or -] 5.7 mm, M = 59.9 mm [+ or -] 3.6 mm, F = 50.7 mm [+ or -] 3.1 mm). When comparing the average measurement from the lateral acromion to the lateral greater tuberosity (e.g., glenohumeral joint relationship # 4) with the results of Takase and associates, there is a significant difference. Takase and associates reported 16.8 mm [+ or -] 5.9 mm, while the results of the current study found an average of 25.2 mm [+ or -] 4.9 mm. This mean difference can be attributed to different measurement techniques: specifically, Takase and associates positioned patients in the supine position with the arm in 0[degrees] abduction, 0[degrees] extension, and 0[degrees] of external rotation, while the current study positioned the arm in 10[degrees] abduction. Additionally, Takase and associates recorded measurements from radiographs, while the current study utilized digital CT scans.

These humeral measurements may be useful for biomechanical computer modeling and have implications on computer navigation and surgical implant positioning and also shoulder arthroplasty prosthesis design, particularly as each relates to soft tissue tensioning (given that, joint stability is best achieved and maintained after shoulder arthroplasty by restoring the native soft tissue tensioning, and native soft tissue tensioning is best restored by implanting a prosthesis that restores the patient's humeral anatomy). (1,5,6,19,23,24) Future work should evaluate if the observed anatomic variability of the proximal humerus in both male and female shoulders can be accommodated by contemporary "fourth generation" shoulder arthroplasty prostheses due to the observed binomial distribution of many of these humeral measurements.

These glenoid and scapula measurements may be useful for rTSA baseplate positioning (using standard instrumentation, patient-specific instruments, or computer navigation) to avoid scapular notching while also maximizing surface contact area in male and female patients. The recent expansion in usage of rTSA has led to new guidelines being established for implant positioning to avoid humeral liner impingement and scapular notching and aseptic glenoid loosening. (25-34) However, with few exceptions, shoulder arthroplasty implantation guidelines are generic (1,3,5-6,18-19,24,31,33) or specific (23,25,27-32,34,35) to individual prosthesis designs rather than to being specific to any particular gender or morphology. As the majority of rTSA recipients are female, rTSA baseplates should be designed to accommodate these smaller and thinner glenoids. Previous work has demonstrated that shorter glenoid necks and higher scapular neck angles predispose patients to a greater risk of scapular notching (25,27,30-32); this study reports no significant difference in glenoid neck length or scapular neck angle between males and females and may explain why male and female scapular notching rates are reported to be similar. (30) Furthermore, several studies (25-32,34) have found that positioning the glenoid implant more distally can significantly improve range of motion and reduce the risk of notching regardless of the patients scapular neck angle. However, little information is available regarding the minimum contact area necessary for rTSA baseplate fixation; this anatomic data on glenoid size and shape may be helpful to establish those limits.

These acromion measurements and glenohumeral joint spatial relationships may be useful to improve our understanding of shoulder kinematics, particularly related to how the deltoid moment arms change with gender and morphology. Acromion size and width were observed to be significantly different between male and female scapula; as the middle and posterior heads of the deltoid originate on the acromion and scapular spine, acromion size can influence the magnitude of the deltoid's moment arms, the degree of wrapping around the greater tuberosity of the humerus, and its line of action at various joint positions. In this study, male shoulders were noted to have significantly larger deltoid moment arms than female shoulders; however, no difference was noted in deltoid wrapping (as measured by the angle between acromion and the top of greater tuberosity). Acromial thickness was also observed to be significantly different between male and female scapula; this data relates to the strength of the acromion, and it may be useful to predict acromial stress fractures, a common complication of rTSA. Future work should investigate if certain acromion morphologies impart greater deltoid efficiency (e.g., larger deltoid moment arms) and determine if there is a minimum cross-sectional area required to prevent acromial and scapula stress fractures with rTSA. If so, these anatomic measurements may be a cost-effective preoperative surgical planning tool or a parameter utilized intraoperatively with computer navigation to predict functional performance and quantify a patient's rTSA complication risk.

Additionally, the coracoid position data relative to the glenoid and greater tuberosity may be useful for assessing medial glenoid wear. Previous work has demonstrated that glenoid wear can shorten the rotator cuff muscles with both aTSA and rTSA, (36-38) decrease deltoid wrapping with rTSA, (36) and also increase the instability rate with rTSA by causing the deltoid to distract the humeral component off the glenosphere. (36,39) Given that no difference was observed in the coracoid base-glenoid distance (scapula dimension #7) between male and female scapula, the mean and variation of this measurement may be useful for surgeons to identify medial glenoid wear preoperatively with AP radiographs or intraoperatively using computer navigation. Specifically, if the coracoid base-glenoid distance was measured and found to be a negative number, it is likely that the patient has some amount of glenoid wear. Alternatively, as the coracoid position relative to the greater tuberosity of the humeral head (glenohumeral joint relationship #3) is very consistent (COV of 10.9% for females and 13.7% for males), this measurement may also be useful to identify medial glenoid wear preoperatively with AP radiographs or intraoperatively using computer navigation. Specifically, if the distance between the lateral coracoid and lateral portion of the greater tuberosity is measured to be two standard deviations from the mean (32.5 mm for males and 27.2 mm for females), it is likely that the patient has significant glenoid wear.

This anatomic study of male and female shoulders has several limitations. First, all measurements were made digitally from the 3D CT-reconstructed bone model rather than directly from the retrieved bones; additionally, measurements were made from the bone models and do not simulate the thickness of the articular cartilage. Second, the glenohumeral joint spatial relationships were measured by digitally manipulating each 3D reconstructed bone model to ensure all bones were positioned identically in 10[degrees] abduction with 3 mm between the humeral head and glenoid rather than externally positioning each patient identically at the time of imaging; as a result, some of the patient's passive relationships may have been slightly altered. Third, while the male and female CT scans were matched for age and BMI, information on race and ethnicity was not available and therefore could not be compared. Finally, no information was available on patient pathology; therefore, differences in morphology as a function of pathology could not be determined.

Conclusions

This CT reconstruction anatomic study of male and female shoulders demonstrates numerous significant gender differences in the morphological variability of the humerus, glenoid and scapula, and also the spatial relationship of these bones. An improved understanding of these observed gender differences has utility for shoulder arthroplasty prosthesis design, computer navigation, intra-operative implant and surgical positioning, and may also be useful to the orthopaedic surgeon during surgical preoperative planning.

Conflict of Interest Statement

Amanda Jacobson, B.S., Matthew A. Hamilton, Ph.D., Alexander Greene, B.S., and Christopher P. Roche, M.S., M.B.A., are employees of Exactech Inc. Gregory J. Gilot, M.D., Pierre-Henri Flurin, M.D., Thomas W. Wright, M.D., and Joseph D. Zuckerman, M.D. are consultants for Exactech, Inc.

References

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Amanda Jacobson, B.S., Gregory J. Gilot, M.D., Matthew A. Hamilton, Ph.D., Alexander Greene, B.S., Pierre-Henri Flurin, M.D., Thomas W. Wright, M.D., Joseph D. Zuckerman, M.D., and Christopher P. Roche, M.S., M.B.A.

Amanda Jacobson, B.S., Matthew A. Hamilton, Ph.D., Alexander Greene, B.S., and Christopher P. Roche, M.S., M.B.A., Exactech, Inc., Gainesville, Florida. Gregory J. Gilot, M.D., Chairman, Department of Orthopaedic Surgery and Director, Orthopaedic and Rheumatologic Center, Cleveland Clinic Florida, Weston, Florida. Pierre-Henri Flurin, M.D., Bordeaux-Merignac Clinique du Sport, Merignac, France. Thomas W. Wright, M.D., Department of Orthopaedics and Rehabilitation, University of Florida, Gainesville, Florida. Joseph D. Zuckerman, M.D., Department of Orthopaedic Surgery, Hospital for Joint Diseases, NYU Langone Medical Center, New York, New York.

Correspondence: Christopher P. Roche, M.S., M.B.A., Exactech, Inc., 2320 NW 66th Court, Gainesville, Florida 32653; chris. roche@exac.com.

Caption: Figure 1 CT reconstructions of female (pink/blue) and male (green/yellow) shoulders.

Caption: Figure 2 Glenohumeral joint relationship spatial measurements.

Caption: Figure 3 Humeral measurements 1.

Caption: Figure 4 Humeral measurements 2.

Caption: Figure 5 Humeral measurements 3.

Caption: Figure 6 Scapula measurements 1.

Caption: Figure 7 Scapula measurements 2.

Caption: Figure 8 Scapula measurements 3.

Caption: Figure 9 Scapula measurements 4.

Table 1 Comparison of Average Glenohumeral Joint Scapular Plane
Measurements: Female Versus Male

                                            All
Anatomic Parameter                       Shoulders
(mm unless noted)

Dimension 1: Base of Coracoid        56.6 [+ or -] 5.1
to Lateral Greater Tuberosity

Dimension 2: Center of Glenoid       55.1 [+ or -] 5.3
to Lateral Greater Tuberosity

Dimension 3: Lateral Coracoid        39.4 [+ or -] 5.2
to Lateral Greater Tuberosity

Dimension 4: Lateral Acromion        25.2 [+ or -] 4.9
to Lateral Greater Tuberosity

Dimension 5: Center of Glenoid       15.7 [+ or -] 4.6
to Lateral Coracoid

Dimension 6: Lateral Acromion        18.6 [+ or -] 5.1
to Top of Greater Tuberosity

Dimension 7: Lateral Acromion        38.2 [+ or -] 6.3
to Lateral Greater Tuberosity

Dimension 8: Humeral Head            14.7 [+ or -] 6.4
Center to Lateral Coracoid

Dimension 9: Humeral Head            33.9 [+ or -] 4.5
Center to Lateral Acromion

Dimension 10: Angle between      54.8 [+ or -] 7.7[degrees]
Acromion and Top of Greater

Tuberosity (degrees)

Dimension 11: Lateral Acromion       23.3 [+ or -] 5.6
to Top of Greater Tuberosity

Dimension 12: Humeral Head            5.4 [+ or -] 5.0
Center to Lateral Greater
Tuberosity

Dimension 13: Humeral Head           20.6 [+ or -] 3.1
Center to Top of Greater
Tuberosity

Dimension 14: Deltoid                12.2 [+ or -] 4.9
Tuberosity to Lateral Greater
Tuberosity

Dimension 15: Center of              29.9 [+ or -] 4.4
Glenoid to Lateral Acromion

Dimension 16: Middle Deltoid         27.5 [+ or -] 2.7
Abductor Moment Arm

Anatomic Parameter                         Female
(mm unless noted)

Dimension 1: Base of Coracoid        53.4 [+ or -] 4.4
to Lateral Greater Tuberosity

Dimension 2: Center of Glenoid       51.3 [+ or -] 3.3
to Lateral Greater Tuberosity

Dimension 3: Lateral Coracoid        37.4 [+ or -] 5.1
to Lateral Greater Tuberosity

Dimension 4: Lateral Acromion        23.3 [+ or -] 3.6
to Lateral Greater Tuberosity

Dimension 5: Center of Glenoid       13.7 [+ or -] 3.9
to Lateral Coracoid

Dimension 6: Lateral Acromion        17.3 [+ or -] 3.9
to Top of Greater Tuberosity

Dimension 7: Lateral Acromion        35.3 [+ or -] 4.6
to Lateral Greater Tuberosity

Dimension 8: Humeral Head            12.4 [+ or -] 4.8
Center to Lateral Coracoid

Dimension 9: Humeral Head            31.2 [+ or -] 2.3
Center to Lateral Acromion

Dimension 10: Angle between      56.0 [+ or -] 6.5[degrees]
Acromion and Top of Greater

Tuberosity (degrees)

Dimension 11: Lateral Acromion       21.6 [+ or -] 3.9
to Top of Greater Tuberosity

Dimension 12: Humeral Head            5.1 [+ or -] 5.0
Center to Lateral Greater
Tuberosity

Dimension 13: Humeral Head           19.0 [+ or -] 2.5
Center to Top of Greater
Tuberosity

Dimension 14: Deltoid                11.8 [+ or -] 4.8
Tuberosity to Lateral Greater
Tuberosity

Dimension 15: Center of              28.0 [+ or -] 3.1
Glenoid to Lateral Acromion

Dimension 16: Middle Deltoid         25.7 [+ or -] 1.6
Abductor Moment Arm

Anatomic Parameter                          Male
(mm unless noted)

Dimension 1: Base of Coracoid        59.8 [+ or -] 3.7
to Lateral Greater Tuberosity

Dimension 2: Center of Glenoid       59.0 [+ or -] 3.9
to Lateral Greater Tuberosity

Dimension 3: Lateral Coracoid        41.5 [+ or -] 4.5
to Lateral Greater Tuberosity

Dimension 4: Lateral Acromion        27.1 [+ or -] 5.3
to Lateral Greater Tuberosity

Dimension 5: Center of Glenoid       17.6 [+ or -] 4.5
to Lateral Coracoid

Dimension 6: Lateral Acromion        19.9 [+ or -] 5.9
to Top of Greater Tuberosity

Dimension 7: Lateral Acromion        41.2 [+ or -] 6.5
to Lateral Greater Tuberosity

Dimension 8: Humeral Head            17.1 [+ or -] 6.9
Center to Lateral Coracoid

Dimension 9: Humeral Head            36.6 [+ or -] 4.5
Center to Lateral Acromion

Dimension 10: Angle between      53.6 [+ or -] 8.7[degrees]
Acromion and Top of Greater

Tuberosity (degrees)

Dimension 11: Lateral Acromion       24.9 [+ or -] 6.4
to Top of Greater Tuberosity

Dimension 12: Humeral Head            5.7 [+ or -] 5.0
Center to Lateral Greater
Tuberosity

Dimension 13: Humeral Head           22.2 [+ or -] 2.8
Center to Top of Greater
Tuberosity

Dimension 14: Deltoid                12.7 [+ or -] 5.1
Tuberosity to Lateral Greater
Tuberosity

Dimension 15: Center of              31.9 [+ or -] 4.7
Glenoid to Lateral Acromion

Dimension 16: Middle Deltoid         29.2 [+ or -] 2.4
Abductor Moment Arm

                                      P-value
Anatomic Parameter               (Male vs. Female)
(mm unless noted)

Dimension 1: Base of Coracoid        < 0.0001
to Lateral Greater Tuberosity

Dimension 2: Center of Glenoid       < 0.0001
to Lateral Greater Tuberosity

Dimension 3: Lateral Coracoid         0.0006
to Lateral Greater Tuberosity

Dimension 4: Lateral Acromion         0.0005
to Lateral Greater Tuberosity

Dimension 5: Center of Glenoid        0.0002
to Lateral Coracoid

Dimension 6: Lateral Acromion         0.0295
to Top of Greater Tuberosity

Dimension 7: Lateral Acromion        < 0.0001
to Lateral Greater Tuberosity

Dimension 8: Humeral Head             0.0010
Center to Lateral Coracoid

Dimension 9: Humeral Head            < 0.0001
Center to Lateral Acromion

Dimension 10: Angle between           0.1885
Acromion and Top of Greater

Tuberosity (degrees)

Dimension 11: Lateral Acromion        0.0088
to Top of Greater Tuberosity

Dimension 12: Humeral Head            0.5976
Center to Lateral Greater
Tuberosity

Dimension 13: Humeral Head           < 0.0001
Center to Top of Greater
Tuberosity

Dimension 14: Deltoid                 0.4175
Tuberosity to Lateral Greater
Tuberosity

Dimension 15: Center of              < 0.0001
Glenoid to Lateral Acromion

Dimension 16: Middle Deltoid         < 0.0001
Abductor Moment Arm

Table 2 Comparison of Average Humeral Measurements: Female
Versus Male

Anatomic Parameter (mm unless noted)          All Humeri

Dimension 1: HH Diameter                   46.8 [+ or -] 4.2

Dimension 2: HH Thickness                  19.5 [+ or -] 2.5

Dimension 3: Distance from top of         139.1 [+ or -] 9.9
HH to Deltoid Insertion

Dimension 4: HH Neck Angle                134.5 [+ or -] 5.1

Dimension 5: HH Medial Offset              8.1 [+ or -] 3.3

Dimension 6: HH Posterior Offset           3.2 [+ or -] 2.3

Dimension 7: Total HH Offset               9.0 [+ or -] 3.4

Dimension 8: Center of HH to Lesser        25.3 [+ or -] 3.5
Tuberosity

Dimension 9: Center of HH to               22.4 [+ or -] 2.7
Greater Tuberosity

Dimension 10: HH Retroversion         26.7 [+ or -] 12.1[degrees]
(degrees)

Dimension 11: Humeral IM Diameter          14.0 [+ or -] 3.0
(75 mm)

Dimension 12: Humeral Outer                23.1 [+ or -] 3.5
Diameter (75 mm)

Dimension 13: Humeral IM Diameter          10.6 [+ or -] 2.4
(Deltoid Insertion)

Dimension 14: Humeral Outer                21.4 [+ or -] 2.9
Diameter (Deltoid Insertion)

Dimension 15: Humeral IM Diameter          10.4 [+ or -] 2.4
(150 mm)

Dimension 16: Humeral Outer                21.4 [+ or -] 2.9
Diameter (150 mm)

Dimension 17: Humeral IM Diameter          9.1 [+ or -] 1.9
(225 mm)

Dimension 18: Humeral Outer                19.2 [+ or -] 2.6
Diameter (225 mm)

Dimension 19: Humerus Length              321.1 [+ or -] 21.3

HH Articular Surface Area                  3465 [+ or -] 633
([mm.sup.2])

Offset Between IM and Outer                0.9 [+ or -] 0.5
Diameters (Deltoid Tuberosity)

Offset Between IM and Outer                0.8 [+ or -] 0.5
Diameters (75 mm)

Offset Between IM and Outer                0.9 [+ or -] 0.6
Diameters (150 mm)

Offset Between IM and Outer                0.6 [+ or -] 0.3
Diameters (225 mm)

Anatomic Parameter (mm unless noted)            Female

Dimension 1: HH Diameter                   43.7 [+ or -] 2.3

Dimension 2: HH Thickness                  17.9 [+ or -] 1.9

Dimension 3: Distance from top of         134.2 [+ or -] 7.6
HH to Deltoid Insertion

Dimension 4: HH Neck Angle                134.3 [+ or -] 5.2

Dimension 5: HH Medial Offset              7.6 [+ or -] 3.0

Dimension 6: HH Posterior Offset           2.5 [+ or -] 2.0

Dimension 7: Total HH Offset               8.3 [+ or -] 2.8

Dimension 8: Center of HH to Lesser        22.9 [+ or -] 2.7
Tuberosity

Dimension 9: Center of HH to               21.1 [+ or -] 2.5
Greater Tuberosity

Dimension 10: HH Retroversion         29.4 [+ or -] 11.1[degrees]
(degrees)

Dimension 11: Humeral IM Diameter          11.9 [+ or -] 2.1
(75 mm)

Dimension 12: Humeral Outer                20.4 [+ or -] 2.2
Diameter (75 mm)

Dimension 13: Humeral IM Diameter          9.4 [+ or -] 2.0
(Deltoid Insertion)

Dimension 14: Humeral Outer                19.2 [+ or -] 1.8
Diameter (Deltoid Insertion)

Dimension 15: Humeral IM Diameter          9.2 [+ or -] 1.8
(150 mm)

Dimension 16: Humeral Outer                19.2 [+ or -] 1.9
Diameter (150 mm)

Dimension 17: Humeral IM Diameter          8.5 [+ or -] 1.6
(225 mm)

Dimension 18: Humeral Outer                17.1 [+ or -] 1.7
Diameter (225 mm)

Dimension 19: Humerus Length              307.1 [+ or -] 15.8

HH Articular Surface Area                  3003 [+ or -] 329
([mm.sup.2])

Offset Between IM and Outer                0.8 [+ or -] 0.5
Diameters (Deltoid Tuberosity)

Offset Between IM and Outer                0.8 [+ or -] 0.4
Diameters (75 mm)

Offset Between IM and Outer                0.8 [+ or -] 0.4
Diameters (150 mm)

Offset Between IM and Outer                0.5 [+ or -] 0.3
Diameters (225 mm)

Anatomic Parameter (mm unless noted)             Male

Dimension 1: HH Diameter                   49.9 [+ or -] 3.3

Dimension 2: HH Thickness                  21.0 [+ or -] 2.0

Dimension 3: Distance from top of         143.9 [+ or -] 9.6
HH to Deltoid Insertion

Dimension 4: HH Neck Angle                134.6 [+ or -] 4.9

Dimension 5: HH Medial Offset              8.7 [+ or -] 3.6

Dimension 6: HH Posterior Offset           3.8 [+ or -] 2.4

Dimension 7: Total HH Offset               9.7 [+ or -] 3.8

Dimension 8: Center of HH to Lesser        27.8 [+ or -] 2.2
Tuberosity

Dimension 9: Center of HH to               23.8 [+ or -] 2.1
Greater Tuberosity

Dimension 10: HH Retroversion         24.1 [+ or -] 12.7[degrees]
(degrees)

Dimension 11: Humeral IM Diameter          16.2 [+ or -] 2.1
(75 mm)

Dimension 12: Humeral Outer                25.8 [+ or -] 2.4
Diameter (75 mm)

Dimension 13: Humeral IM Diameter          11.7 [+ or -] 2.1
(Deltoid Insertion)

Dimension 14: Humeral Outer                23.5 [+ or -] 1.9
Diameter (Deltoid Insertion)

Dimension 15: Humeral IM Diameter          11.5 [+ or -] 2.4
(150 mm)

Dimension 16: Humeral Outer                23.7 [+ or -] 1.9
Diameter (150 mm)

Dimension 17: Humeral IM Diameter          9.8 [+ or -] 1.9
(225 mm)

Dimension 18: Humeral Outer                21.2 [+ or -] 1.6
Diameter (225 mm)

Dimension 19: Humerus Length              335.1 [+ or -] 16.3

HH Articular Surface Area                   3926 [+ or -]518
([mm.sup.2])

Offset Between IM and Outer                1.0 [+ or -] 0.5

Diameters (Deltoid Tuberosity)

Offset Between IM and Outer                0.9 [+ or -] 0.5
Diameters (75 mm)

Offset Between IM and Outer                1.1 [+ or -] 0.7
Diameters (150 mm)

Offset Between IM and Outer                0.6 [+ or -] 0.3
Diameters (225 mm)

                                           P-value
Anatomic Parameter (mm unless noted)  (Male vs. Female)

Dimension 1: HH Diameter                  < 0.0001

Dimension 2: HH Thickness                 < 0.0001

Dimension 3: Distance from top of         < 0.0001
HH to Deltoid Insertion

Dimension 4: HH Neck Angle                 0.8069

Dimension 5: HH Medial Offset              0.1423

Dimension 6: HH Posterior Offset           0.0164

Dimension 7: Total HH Offset               0.0709

Dimension 8: Center of HH to Lesser       < 0.0001
Tuberosity

Dimension 9: Center of HH to              < 0.0001
Greater Tuberosity

Dimension 10: HH Retroversion              0.0610
(degrees)

Dimension 11: Humeral IM Diameter         < 0.0001
(75 mm)

Dimension 12: Humeral Outer               < 0.0001
Diameter (75 mm)

Dimension 13: Humeral IM Diameter         < 0.0001
(Deltoid Insertion)

Dimension 14: Humeral Outer               < 0.0001
Diameter (Deltoid Insertion)

Dimension 15: Humeral IM Diameter         < 0.0001
(150 mm)

Dimension 16: Humeral Outer               < 0.0001
Diameter (150 mm)

Dimension 17: Humeral IM Diameter          0.0030
(225 mm)

Dimension 18: Humeral Outer               < 0.0001
Diameter (225 mm)

Dimension 19: Humerus Length              < 0.0001

HH Articular Surface Area                 < 0.0001
([mm.sup.2])

Offset Between IM and Outer                0.1925
Diameters (Deltoid Tuberosity)

Offset Between IM and Outer                0.2683
Diameters (75 mm)

Offset Between IM and Outer                0.0401
Diameters (150 mm)

Offset Between IM and Outer                0.0659
Diameters (225 mm)

Table 3 Comparison of Average Scapular Measurements: Female Versus
Male

Anatomic Parameter (all values mm             All Scapula
unless noted)

Dimension 1: Glenoid Neck Length            9.5 [+ or -] 2.8

Dimension 2: Coracoid Tip-Glenoid          16.4 [+ or -] 4.7
Distance

Dimension 3: Lateral                       29.1 [+ or -] 4.8
Acromion-Glenoid Distance

Dimension 4: Glenoid Articular             40.7 [+ or -] 13.4
Curvature, Radius

Dimension 5: Scapular Neck Angle      116.1 [+ or -] 12.0[degrees]
(degrees)

Dimension 6: Glenoid Inclination       96.4 [+ or -] 5.2[degrees]
(degrees)

Dimension 7: Coracoid Base-Glenoid          1.1 [+ or -] 2.9
Distance

Dimension 8: Glenoid Height                38.1 [+ or -] 4.5

Dimension 9: Glenoid Upper Width           23.6 [+ or -] 4.2

Dimension 10: Glenoid Lower Width          29.6 [+ or -] 4.0

Dimension 11: Acromion Thickness           14.4 [+ or -] 2.9
(AP width at spine)

Dimension 12: Acromion Length              49.2 [+ or -] 5.6

Dimension 13: Acromion Thickness           10.6 [+ or -] 3.9
(SI width lateral border)

Dimension 14: PI Acromion-Glenoid          42.7 [+ or -] 5.1
Distance

Dimension 15: Distance from                37.6 [+ or -] 3.8
Acromial Plane to Center of Glenoid

Dimension 16: Acromial-Glenoid        53.2 [+ or -] 10.5[degrees]
Angle (degrees)

Dimension 17: PS Acromion-Glenoid           3.4 [+ or -] 4.9
Distance

Dimension 18: Glenoid Version          96.2 [+ or -] 5.5[degrees]
(degrees)

Dimension 19: Fulcrum Axis             89.9 [+ or -] 5.3[degrees]
(degrees)

Glenoid Height/Upper Width Ratio           1.64 [+ or -] 0.21

Glenoid Height/Lower Width Ratio           1.29 [+ or -] 0.10

Glenoid Articular Surface Area              814 [+ or -] 209
([mm.sup.2])

Anatomic Parameter (all values mm                Female
unless noted)

Dimension 1: Glenoid Neck Length            9.2 [+ or -] 2.6

Dimension 2: Coracoid Tip-Glenoid          14.6 [+ or -] 3.7
Distance

Dimension 3: Lateral                       27.5 [+ or -] 2.9
Acromion-Glenoid Distance

Dimension 4: Glenoid Articular             39.5 [+ or -] 17.4
Curvature, Radius

Dimension 5: Scapular Neck Angle      114.2 [+ or -] 10.8[degrees]
(degrees)

Dimension 6: Glenoid Inclination       97.0 [+ or -] 5.5[degrees]
(degrees)

Dimension 7: Coracoid Base-Glenoid          1.6 [+ or -] 1.7
Distance

Dimension 8: Glenoid Height                35.1 [+ or -] 2.5

Dimension 9: Glenoid Upper Width           21.9 [+ or -] 3.7

Dimension 10: Glenoid Lower Width          27.0 [+ or -] 2.7

Dimension 11: Acromion Thickness           12.5 [+ or -] 2.2
(AP width at spine)

Dimension 12: Acromion Length              45.4 [+ or -] 4.5

Dimension 13: Acromion Thickness            9.2 [+ or -] 1.2
(SI width lateral border)

Dimension 14: PI Acromion-Glenoid          39.5 [+ or -] 3.4
Distance

Dimension 15: Distance from                35.2 [+ or -] 2.8
Acromial Plane to Center of Glenoid

Dimension 16: Acromial-Glenoid         53.3 [+ or -] 9.2[degrees]
Angle (degrees)

Dimension 17: PS Acromion-Glenoid           3.1 [+ or -] 4.4
Distance

Dimension 18: Glenoid Version          95.0 [+ or -] 4.0[degrees]
(degrees)

Dimension 19: Fulcrum Axis             89.5 [+ or -] 4.5[degrees]
(degrees)

Glenoid Height/Upper Width Ratio           1.63 [+ or -] 0.20

Glenoid Height/Lower Width Ratio           1.30 [+ or -] 0.09

Glenoid Articular Surface Area              666 [+ or -] 106
([mm.sup.2])

Anatomic Parameter (all values mm                 Male
unless noted)

Dimension 1: Glenoid Neck Length            9.8 [+ or -] 3.0

Dimension 2: Coracoid Tip-Glenoid          18.2 [+ or -] 4.9
Distance

Dimension 3: Lateral                       30.7 [+ or -] 5.8
Acromion-Glenoid Distance

Dimension 4: Glenoid Articular             41.8 [+ or -] 7.6
Curvature, Radius

Dimension 5: Scapular Neck Angle      118.1 [+ or -] 12.9[degrees]
(degrees)

Dimension 6: Glenoid Inclination       95.8 [+ or -] 4.9[degrees]
(degrees)

Dimension 7: Coracoid Base-Glenoid          0.6 [+ or -] 3.6
Distance

Dimension 8: Glenoid Height                41.1 [+ or -] 4.1

Dimension 9: Glenoid Upper Width           25.3 [+ or -] 4.0

Dimension 10: Glenoid Lower Width          32.1 [+ or -] 3.4

Dimension 11: Acromion Thickness           16.2 [+ or -] 2.3
(AP width at spine)

Dimension 12: Acromion Length              53.1 [+ or -] 3.5

Dimension 13: Acromion Thickness           11.9 [+ or -] 5.1
(SI width lateral border)

Dimension 14: PI Acromion-Glenoid          45.9 [+ or -] 4.5
Distance

Dimension 15: Distance from                40.1 [+ or -] 3.1
Acromial Plane to Center of Glenoid

Dimension 16: Acromial-Glenoid        53.0 [+ or -] 11.8[degrees]
Angle (degrees)

Dimension 17: PS Acromion-Glenoid           3.7 [+ or -] 5.5
Distance

Dimension 18: Glenoid Version          97.4 [+ or -] 6.6[degrees]
(degrees)

Dimension 19: Fulcrum Axis             90.3 [+ or -] 6.1[degrees]
(degrees)

Glenoid Height/Upper Width Ratio           1.65 [+ or -] 0.23

Glenoid Height/Lower Width Ratio           1.29 [+ or -] 0.12

Glenoid Articular Surface Area              962[+ or -] 179
([mm.sup.2])

                                           P-value
Anatomic Parameter (all values mm     (Male vs. Female)
unless noted)

Dimension 1: Glenoid Neck Length           0.2989

Dimension 2: Coracoid Tip-Glenoid          0.0006
Distance

Dimension 3: Lateral                       0.0038
Acromion-Glenoid Distance

Dimension 4: Glenoid Articular             0.4601
Curvature, Radius

Dimension 5: Scapular Neck Angle           0.1631
(degrees)

Dimension 6: Glenoid Inclination           0.3253
(degrees)

Dimension 7: Coracoid Base-Glenoid         0.1590
Distance

Dimension 8: Glenoid Height               < 0.0001

Dimension 9: Glenoid Upper Width           0.0003

Dimension 10: Glenoid Lower Width         < 0.0001

Dimension 11: Acromion Thickness          < 0.0001
(AP width at spine)

Dimension 12: Acromion Length             < 0.0001

Dimension 13: Acromion Thickness           0.0022
(SI width lateral border)

Dimension 14: PI Acromion-Glenoid         < 0.0001
Distance

Dimension 15: Distance from               < 0.0001
Acromial Plane to Center of Glenoid

Dimension 16: Acromial-Glenoid             0.8864
Angle (degrees)

Dimension 17: PS Acromion-Glenoid          0.6105
Distance

Dimension 18: Glenoid Version              0.0614
(degrees)

Dimension 19: Fulcrum Axis                 0.5373
(degrees)

Glenoid Height/Upper Width Ratio           0.6443

Glenoid Height/Lower Width Ratio           0.4728

Glenoid Articular Surface Area            < 0.0001
([mm.sup.2])

Table 4 Comparison of Published Humeral Measurements

Anatomic Parameter                       HH                  HH
(mm unless noted)                     Diameter            Thickness

Boileau, et al. (1) (N = 65)     46.2 [+ or -] 5.4    15.2 [+ or -] 1.6
Hertel, et al. (3) (N = 200)     44.5 [+ or -] 4.0    17.0 [+ or -] 1.7
Iannotti, et al. (4) (N = 140)           NR            19 [+ or -] 2.4
Roberts, et al. (5) (N = 39)     50.3 [+ or -] 1.01          NR
Robertson, et al. (6) (N = 60)     46 [+ or -] 4        19 [+ or -] 2
Takase, et al. (7) (N = 471)     54.3 [+ or -] 5.4           NR
Current Study (N = 74)           46.8 [+ or -] 4.2    19.5 [+ or -] 2.5

Anatomic Parameter                    HH Neck            HH Medial
(mm unless noted)                Angle ([degrees])         Offset

Boileau, et al. (1) (N = 65)     129.6 [+ or -] 2.9   6.9 [+ or -] 2.0
Hertel, et al. (3) (N = 200)     137.0 [+ or -] 3.6   6.0 [+ or -] 1.8
Iannotti, et al. (4) (N = 140)     135 [+ or -] 5            NR
Roberts, et al. (5) (N = 39)             NR                  NR
Robertson, et al. (6) (N = 60)     131 [+ or -] 3       7 [+ or -] 2
Takase, et al. (7) (N = 471)     140.4 [+ or -] 4.1          NR
Current Study (N = 74)           134.5 [+ or -] 5.1   8.1 [+ or -] 3.3

                                         HH
Anatomic Parameter                   Posterior
(mm unless noted)                      Offset

Boileau, et al. (1) (N = 65)      2.6 [+ or -] 1.8
Hertel, et al. (3) (N = 200)      1.4 [+ or -] 1.4
Iannotti, et al. (4) (N = 140)           NR
Roberts, et al. (5) (N = 39)      4.7 [+ or -] 1.1
Robertson, et al. (6) (N = 60)      2 [+ or -] 2
Takase, et al. (7) (N = 471)             NR
Current Study (N = 74)            3.2 [+ or -] 2.3

Anatomic Parameter                       HH
(mm unless noted)                   Retroversion

Boileau, et al. (1) (N = 65)     17.9 [+ or -] 13.7
Hertel, et al. (3) (N = 200)     23.3 [+ or -] 11.8
Iannotti, et al. (4) (N = 140)           NR
Roberts, et al. (5) (N = 39)     21.4 [+ or -] 4.6
Robertson, et al. (6) (N = 60)     19 [+ or -] 6
Takase, et al. (7) (N = 471)             NR
Current Study (N = 74)           26.7 [+ or -] 12.1

Anatomic Parameter                     Humerus
(mm unless noted)                      Length

Boileau, et al. (1) (N = 65)        Not reported
Hertel, et al. (3) (N = 200)     316.0 [+ or -] 23.0
Iannotti, et al. (4) (N = 140)           NR
Roberts, et al. (5) (N = 39)             NR
Robertson, et al. (6) (N = 60)     330 [+ or -] 30
Takase, et al. (7) (N = 471)             NR
Current Study (N = 74)           321.1 [+ or -] 21.3

NR = Not reported.

Table 5 Comparison of Published Scapular Measurements

Anatomic Parameter
(mm unless noted)                           Glenoid Height

Bryce, et al. (9) (N = 40)                       44.9
Checroun, et al. (10) (N = 412)            37.9 [+ or -] 2.7
Churchill, et al. (11) (N = 344)                 35.0
Iannotti, et al. (4) (N = 140)             39.0 [+ or -] 3.7
Kwon, et al. (13) (N = 12)                       39.1
Ljungquist, et al. (14) (N = 100)                35.2
Mallon, et al. (15) (N = 28)                     35.0
Merril, et al. (22) (N = 368, 184 pairs)   35.4 [+ or -] 2.2
Ohl, et al. (16) (N = 43)                        35.3
Von Schroder, et al. (17) (N = 30)               36.4
Current Study (N = 74)                     38.1 [+ or -] 4.5

Anatomic Parameter
(mm unless noted)                            Glenoid Width

Bryce, et al. (9) (N = 40)                       31.1
Checroun, et al. (10) (N = 412)            29.3 [+ or -] 2.4
Churchill, et al. (11) (N = 344)                 25.7
Iannotti, et al. (4) (N = 140)             29.0 [+ or -] 3.1
Kwon, et al. (13) (N = 12)                       25.2
Ljungquist, et al. (14) (N = 100)                25.3
Mallon, et al. (15) (N = 28)                     24.0
Merril, et al. (22) (N = 368, 184 pairs)   26.1 [+ or -] 3.5
Ohl, et al. (16) (N = 43)                        25.9
Von Schroder, et al. (17) (N = 30)               28.6
Current Study (N = 74)                     29.6 [+ or -] 4.0

Anatomic Parameter
(mm unless noted)                          Version Angle ([degrees])

Bryce, et al. (9) (N = 40)                            NR
Checroun, et al. (10) (N = 412)                       NR
Churchill, et al. (11) (N = 344)                     -1.2
Iannotti, et al. (4) (N = 140)                        NR
Kwon, et al. (13) (N = 12)                           -1.0
Ljungquist, et al. (14) (N = 100)                     NR
Mallon, et al. (15) (N = 28)                         -2.0
Merril, et al. (22) (N = 368, 184 pairs)              NR
Ohl, et al. (16) (N = 43)                            -2.4
Von Schroder, et al. (17) (N = 30)                    NR
Current Study (N = 74)                         -6.2 [+ or -] 5.5

Anatomic Parameter                          Glenoid Height/
(mm unless noted)                          Lower Width Ratio

Bryce, et al. (9) (N = 40)                         NR
Checroun, et al. (10) (N = 412)            1.3 [+ or -] 0.07
Churchill, et al. (11) (N = 344)                   NR
Iannotti, et al. (4) (N = 140)             1.43 [+ or -] 0.02
Kwon, et al. (13) (N = 12)                         NR
Ljungquist, et al. (14) (N = 100)                 1.39
Mallon, et al. (15) (N = 28)                       NR
Merril, et al. (22) (N = 368, 184 pairs)           NR
Ohl, et al. (16) (N = 43)                          NR
Von Schroder, et al. (17) (N = 30)                 NR
Current Study (N = 74)                     1.29 [+ or -] 0.10

NR = Not reported.


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Title Annotation:body mass index
Author:Jacobson, Amanda; Gilot, Gregory J.; Hamilton, Matthew A.; Greene, Alexander; Flurin, Pierre-Henri;
Publication:Bulletin of the NYU Hospital for Joint Diseases
Article Type:Report
Date:Oct 1, 2015
Words:8535
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