Length Of Clavicle Research Articles

Post-mortem estimation of gestational age and maturation of new-borns by CT examination of clavicle length, femoral length and femoral bone nuclei

Various parameters can be used for the estimation of gestational age and maturity with arising challenges in the assessment of decomposed bodies. In order to assess gestational age and thus maturity, the study measured the femoral length, the diameter of the distal femoral epiphysis and the presence of the proximal tibial epiphysis compared to a known clavicle length. The resulting gestational ages were compared and statistically evaluated. As a result, discrepancies between the estimated gestational ages became apparent in some cases when comparing the individual structures to be measured. However, there was a clear tendency towards a lower gestational age calculated based on clavicle length and a higher gestational age calculated based on femoral length and distal femoral epiphysis. With regard to the assessment of maturity, it has been concluded that, if the proximal tibial epiphysis is present, maturity can also be assumed based on the diameter of the distal femoral epiphysis and the length of the femur.

The variance of clavicular surface morphology is predictable: an analysis of dependent and independent metadata variables

BackgroundThe anatomy of the clavicle is specific and varied in reference to its topography and shape. These anatomic characteristics play an important role in the open treatment of clavicle fractures. The complex and variable topography creates challenges for implant placement, contouring, and position. Hardware prominence and irritation does influence the decision for secondary surgical intervention.MethodsComputerized tomographic scans of 350 adult clavicles with the corresponding patients' metadata were acquired and digitized. Morphologic parameters determining the shape of the clavicle were defined and computed for each digitized bone. The extracted morphologic parameters were correlated with patient metadata to analyze the relationship between morphologic variability and patient characteristics.ResultsThe morphologic parameters defining the shape, that is, the radius of the medial and lateral curves, the apparent clavicle height and width, and the clavicle bow position, correlate with the clavicle length. The clavicle length correlates with the patients' height. Gender differences in shape and form were dependent and related to individual height distribution and clavicle length. Asian populations showed a similarly predictable, but shifted, correlation between shape and clavicle length.ConclusionThis anatomic analysis shows that the clavicle shape can be predicted through the clavicle length and patients' stature. Smaller patients have shorter and more curved clavicles, whereas taller patients have longer and less curved clavicles. This correlation will aid surgeons in fracture reduction, implant curvature selection, and in optimal adaptation of clavicle implants, and represents the basis for anatomically accurate solutions for clavicle osteosynthesis.

Correlation Between Stature and Length of Clavicle in Male Population of Central India

Correlation Between Stature and Length of Clavicle in Male Population of Central India

Morphometric parameters of clavicles among adult Black people in Tanzania

Morphological clavicular variation has been studied extensively by orthopaedic surgeons, anatomic and forensic experts to explain developmental, gender and age-related differences. The design of fixation devices for displaced clavicular fracture management depends largely on anatomic characteristics of clavicle. Eighty-one unpaired clavicles of unknown sex were studied, 42 clavicles were of right side and 39 clavicles of left side. All the clavicles were collected from adult cadavers which were dissected in Departments of Anatomy at Muhimbili and Herbert Kairuki Memorial Universities. The length of clavicle was measured by a vernier calliper; the middle point of this length was taken as the point where midclavicular circumference was measured with the help of a measuring thread and the angle of curvature of clavicle was measured by using protractors. The average lengths of the left and right clavicles were 15.23±1.12 cm and 15.43±1.01cm respectively. The average medial angle of curvature of left clavicle was 155.33° ± 4.39°and that of right clavicle was 153.40° ± 3.96°. The mean total angle of curvature of left clavicle was 293.54˚± 9.55°and the average total angle of curvature of right clavicle was 290.05±8.94°. The average midclavicular circumference of left clavicle was 3.88cm ± 0.33cm and that of right clavicle was 3.94cm±0.33cm. The right clavicle was longer than the left clavicle, the average medial angle of curvature of left clavicle was greater than medial angle of right clavicle, the average lateral angle of curvature of left clavicle was more than the average lateral angle of curvature of right clavicle and the mean of midclavicular circumference of right clavicle was greater than that of left clavicle.
 Keywords: Morphometric, clavicle, curvatures, circumference

Reliability of the radiographic views in supine position for evaluation of displaced midshaft clavicle fracture length.

To analyze the agreement of the displaced midshaft clavicle fracture length measurement between each of the supine radiographic position (chest anteroposterior (AP), both clavicle AP, and 20° cephalic tilt clavicle AP view) and computed tomography (CT) scan of the clavicle. Furthermore, the inter- and intraobserver reliability of each radiographic position was analyzed. Prospective cross-sectional study was performed with patients diagnosed with displaced midshaft clavicle fracture treated conservatively. Three views of radiographs and CT scan of clavicle were obtained in supine position after informed consent. The measurement of fractured clavicle length was done by three observers at the time and after 4 weeks interval. Thirty-three patients (25 males and 8 females), with a mean age of 45, were recruited. The agreement between each of the radiographic measurement and CT scan was good. The interobserver reliability was moderate to good for radiographic measurement. The highest intraclass correlation coefficient (ICC) of 0.80-0.81 was shown between the 20° cephalic tilt and the CT scan, followed by the both clavicle AP (0.75-0.77) and the chest AP (0.69-0.75), respectively. There was an excellent intraobserver reliability for all of the radiographic measurement with the ICC 0.92-0.99. The supine radiographs could be a useful option to measure the displaced midshaft clavicle fracture length. The recommended view was the 20° cephalic tilt clavicle AP view in supine position to best evaluate the fractured clavicle length.

The Clavicle Continues to Grow During Adolescence and Early Adulthood.

As more adults undergo surgical fixation of clavicle fractures with improved outcomes, interest is renewed in managing clavicle fractures in adolescents. The medial clavicular physis does not fuse until 23 to 25years of age, but studies report minimal clavicular growth during adolescence-studies that employed cross-sectional methodologies, which cannot not capture growth in patients over time. The assumption that clavicle length at each stage is uniform, as is the final overall length, may not be accurate if the age groups studied comprise various ethnicities, socioeconomic status, or height. We sought to quantify longitudinal clavicular growth on serial radiographs in adolescents and young adults. Our hypothesis was that substantial clavicular growth would be seen beyond the age of 12 years. We conducted a longitudinal case series of non-syndromic patients in a single orthopedic clinic and analyzed serial radiographic images of the clavicles. For ethical reasons, only patients with non-neuromuscular scoliosis and kyphosis (in whom the existing standard of care includes serial thoracic radiographs) were considered for inclusion. Patients ages 10 to 25years old were included in the study if three or more serial thoracic radiographs over a minimum 5years were available that captured the entire length of at least one non-rotated clavicle. Three types of radiographs were included for analysis: digital low-dose-radiation stereoradiographic (EOS Imaging, Paris, France), non-EOS digital, and non-EOS printed. The overall longitudinal growth, yearly growth, and the yearly growth percentage were calculated for each clavicle. Fifty-seven patients (22 male and 35 female) met the inclusion criteria. In male patients, at ages 12 to 15years, the clavicular growth was 4.9mm/year, or 4%/year; at ages 16 to 19years, growth was 3.2mm/year, or 2.4%/year; and at ages 20 to 25years, growth was 1.7mm/year, or 1.1%/year. In female patients, at ages 12 to 15years, growth was 4.7mm/year, or 4%/year; at 16 to 19years, growth was 2.2mm/year, or 1.7%/year; and at ages 20 to 25years, growth was 0.2mm/year or 0.1%/year. We could not detect the age of terminal growth in either sex because growth was ongoing in most patients in the oldest group. We found substantial clavicular growth potential after age 18years, when growth is thought to be nearly finished, as well as remodeling potential even up to age 25years. Further research is needed, but our findings suggest that strategies for managing clavicle fracture in adults may not be applied universally to adolescents and young adults.

Clavicles continue to grow beyond skeletal maturity: radiographic analysis of clavicle length in adolescents and young adults.

There has been minimal research regarding the clavicle's growth and its clinical implications in the late adolescent and early adult population. Previous studies have evaluated postnatal clavicle growth to age 18 without analysing growth through the age of secondary ossification center closure. The purpose of this study was (1) to determine clavicle length and age-related growth in males and females from age 12 to 25 years and (2) to specifically analyse clavicle growth in late adolescence. This was a retrospective analysis of chest radiographs in patients aged 12-25 years. The ruler tool was used to measure clavicle length. Mean values were tabulated for each year of age in males (n = 697) and females (n = 672). Mean right clavicle growth significantly increased from age 12 to 25 in both males and females (P < 0.0001). In males, the increase from age 16 to 25 was 17.5 mm, representing 10.6% of total clavicle length (P < 0.0001). In females, the increase from age 14 to 25 was 7.7 mm, representing 5.2% of total clavicle length (P < 0.0001). We found that from skeletal maturity to the closure of the secondary ossification center, growth was 17.5 mm (10.6% of total clavicle length) in males and 7.7 mm (5.2% of total clavicle length) in females. During their growth spurts, the adolescent male and female clavicle have growth potentials very similar to previous studies of radius growth. Understanding these clavicular growth potentials can influence operative vs. nonoperative management decisions by orthopaedic surgeons. Level of evidence: Level III.

Bilaterally Threaded, Minimal Invasive, Elastic Locking Intramedullary Nailing (ELIN) for the Treatment of Clavicle Fractures.

ObjectiveTo evaluate and present the effectiveness of this innovatively designed, elastic locking intramedullary nail (ELIN) in fixation of clavicle fractures.MethodsThe study included 38 patients from July 2014 to July 2017. All of them received intramedullary fixation treated with ELIN, 22 were males and 16 females. The mean age of the patients was 54 years. There were twenty right‐side and 18 left‐side clavicular fractures. Radiographs were taken to assess the fracture type: 21 were type A, 16 type B, and one type C. General anesthesia or cervical block was given to all patients. A small incision of 3–5 cm was given only to those who needed mini‐open reduction. The administration of ELIN and reduction of the fracture was made sure with a C arm machine. After a follow‐up of 8 to 33 months, the clinical outcomes were assessed and evaluated. The constant scores and disabilities of the arm, shoulder and hand questionnaire (DASH) were used to determine the outcomes and functional status of the patients. The study was done accordingly to the guidelines provided by the ethics committee.ResultsMean operation time was 25.63 min. Mean follow‐up time was 16.5 months. The rate of closed reduction and open reduction was 84% and 16% respectively. There was no shortening of the clavicle. There was no breakage of the nail, though bending of the nail occurred in one patient. Superficial skin infection occurred in three patients at insertion points or the nail tip which was embedded subcutaneously. Skin erosion with nail exposure occurred in a patient with no significant infection. All the other patients had excellent shoulder function. A mini scar was observed in seven patients all the other patients had no scar. Asymmetry was observed in three patients. The mean Constant score was 98.47 and the mean DASH score was 1.55 at the last follow‐up. The implant was removed in all the patients.ConclusionClavicular fractures treated with ELIN is minimally invasive, which presents a safe and novel surgical technique with less complications and a high success rate, excellent aesthetic and quick recovery after surgery. ELIN restores the micro‐dynamic stress at the fracture ends and promotes fracture healing, keeps intact the fracture hematoma and maintains the blood supply, accelerates healing and thus leads to faster osseous healing and better restoration of clavicle length.

Sex-Based Differences in Optimal Tunnel Placement for Acromioclavicular Joint Reconstruction.

Background:Tunnel placement is important for outcomes after acromioclavicular (AC) joint reconstruction, yet little has been written on sex-based differences in optimal tunnel positioning.Hypothesis:No sex-based or anatomic differences will be found in ideal tunnel position based on radiographic measurements.Study Design:Cross-sectional study; Level of evidence, 3.Methods:The records of 2382 patients were retrospectively examined for clavicle radiographs over a 20-year period. A random set of radiographs were reviewed until 200 radiographs from each sex met inclusion criteria per a priori power analysis. Anteroposterior clavicle radiographs were used to collect (1) length from lateral clavicle to lateral coracoid (LCLC), (2) length from lateral clavicle to medial coracoid (LCMC), (3) clavicle length (CL), and (4) clavicular depth at the midcoracoid (MCCD). The Student t test was used to compare differences between male and female patients. The Pearson correlation coefficient was used to measure linear correlations. Variables with a P < .1 were included in a multiple regression model.Results:The cohort included 200 men and 200 women. LCLC and LCMC were significantly greater for men than for women (P < .0001). Clavicle length was significantly correlated with LCLC (r = 0.63; P < .0001) and LCMC (r = 0.74; P < .0001). MCCD was significantly correlated with LCLC (r = 0.32; P < .0001) and LCMC (r = 0.43; P < .0001). The approximate placement for the trapezoid tunnel was found to be 22.1 mm in women and 26.6 mm in men. The approximate placement for the conoid tunnel was found to be 40 mm in women and 46.6 mm in men. The ratios (LCLC:CL and LCMC:CL) were also significantly different between female and male patients. The LCLC:CL was 0.144 in women and 0.154 in men (P < .0001). The LCMC:CL was 0.261 in women and 0.271 in men (P < .0006).Conclusion:Significant sex-based differences are found in the position of the coracoid relative to the lateral edge of the clavicle. Coracoid position relative to the lateral edge of the clavicle is correlated with anatomic parameters, most strongly with clavicle length.

Estimation ofstature from the length of clavicle in adult (post-fusion age) in Saurashtra region of Gujarat

Estimation ofstature from the length of clavicle in adult (post-fusion age) in Saurashtra region of Gujarat

A New Predictor for Patients with Cardiac Implantable Electronic Device in Iatrogenic Pneumothorax: The Clavicle Length Index

A New Predictor for Patients with Cardiac Implantable Electronic Device in Iatrogenic Pneumothorax: The Clavicle Length Index

Long-term follow-up of conservatively treated midshaft clavicular fractures on functional outcome

BackgroundThe aim of this study was to examine the long-term effect of shortening after a midshaft clavicular fracture on strength deficiency in the shoulder. MethodThis study included 18 participants (14 males, 4 females) with a conservatively treated midshaft clavicular fracture. Mean age was 52.2 ± 13.8 years, range 32–76 years). The mean follow-up time was 13.5 ± 0.4 years. Participants filled in a QUICKDASH questionnaire and both clavicle lengths were measured using a caliper. The isometric strengths in internal rotation, external rotation and abduction of both arms were measured with a handheld dynamometer. ResultsAverage shortening of the clavicle in this group was 1.09 cm (SD 0.53). Nearly all strength measurements showed no significant difference between the shortened and the unaffected side. Multiple regression revealed a small (3N per mm length difference) but statistically significant relationship on external rotation between the relative extent of shortening of the clavicle, dominant side of the fracture and the isometric force difference between the unaffected and affected arm, F(2,15) = 5.746, p < .05, adj. R2 = .358. Over 14 years there was a reduction in mean DASH-score of 4.4 (8.8 ± 12.3; current DASH = 4.4 ± 7.7)In this group, long term effects of clavicular shortening were small. Based on these results we conclude that on the long term clavicular shortening will not result in significant strength loss.

Is there a relationship between the lengths of the ipsilateral clavicle and the ulna? An anthropometric and statistical study

Aim: Mathematical relationships between bones in close proximity are useful for determining the proper length of comminuted or severely displaced bones during surgical reconstruction. This study examined the relationship between the lengths of the clavicle and ulna to develop a length propotion formula that can facilitate obtaining the proper length of the clavicle during surgery for displaced and comminuted fractures. Methods: The study enrolled 130 individuals (76 males, 54 females)who were healty for their upper extremities and was seen in our orthopedics outpatient clinic during April 2019 to June 2019. The right and left clavicles and ulnas of each individual were measured. All measurements were peformed by two of the authors in an blinded fashion. Results. Mean overall age was 32.2 years. There were significant correlations between the clavicle and ipsilateral ulnar lengths (p=0.001). However, there was a length difference between the right and left clavicles. The left clavicle was 9.00 ± 2.16 mm longer than the right in males and 7.13 ± 2.03 mm longer in females (p=0.001). There was no significant length difference between the right and left ulnas in either sex (0.84 ± 1.033 mm in males and 0.52 ± 0.818 mm in females). Conclusion. There is a significant ratio between the clavicle and ulna lengths on both the right and left sides in both sexes, but it isn’t the same for males and females. We propose that these length proportion formula can be used for determining the clavicle length for the surgical treatment of comminuted fractures with plates and particularly with nails.

Morphometric Variation of Adult Human Clavicle - A Tool for Gender Determination

Introduction: Bones can reflect the basic framework of human body and provide valuable information about the biological identity of the deceased. They often, survive the morphological alteration, decay/mutation and decomposition insults. An in depth, knowledge and analysis of variation in clavicular length, midclavicular circumference and weight is imperative for both clinical and forensic anthropological perspectives. Objectives: The present study was done to determine morphometric variability of adult human clavicles by using length, weight and midclavicular circumference parameters. Materials and Methods: 300 pairs of adult human clavicles of known sex obtained from cadaveric dissection and bony collections of anatomy department were utilized for the study. The length, weight and midclavicular circumference were measured. The data obtained was statistically analysed. Results: Gender specific statistical analysis for length, weight and midclavicular circumference was found to be highly significant. The side specific significance was found only in male and in female clavicles for weight and midclavicular circumference respectively. No side specific significance found for length of clavicle. Conclusions: The present study provides morphometric data for North Indians and compares observations with other populations. The study establishes that length, weight and midclavicular circumference of clavicle have a dimorphic potential. This fact can play a decisive role in forensic identifications and clinical interventions. The results are of immense significance for anatomists, orthopedic surgeons and the forensic anthropologists in their professional endeavors.

3D planning and surgical navigation of clavicle osteosynthesis using adaptable patient-specific instruments

BackgroundPreoperative three-dimensional planning and intraoperative navigation by patient-specific instruments is a promising method for the exact correction of bone deformities. Nevertheless, disadvantages of current concepts are the missing options of adapting the surgical plan intraoperatively. By providing the surgeons with a controlled length adjustment through the patient-specific instruments, the application area can usefully be expanded in the treatment of clavicle osteosyntheses.MethodsIn three cases, preoperative three-dimensional surgical planning with the intraoperative use of patient-specific instruments was applied. The computer-assisted assessments of clavicle deformities, the preoperative plan, and the design of patient-specific instruments were created on the basis of computed tomography data. Reduction guides for restoring length and rotation according to the mirrored healthy contralateral side were enhanced with adaptable length adjustment functions. The screw thread of the reduction guides enabled temporary distraction of the clavicle fracture fragments and a controlled compression of the optionally used interposed bone block between clavicle fragments.ResultsNavigated clavicle osteosyntheses by enhanced patient-specific instruments was executed uneventful in all three cases. The surgeon was able to adapt clavicle length in a planned axis intraoperatively as clinically desired.ConclusionComputer-assisted planning of clavicle osteosynthesis and surgical navigation with additional adaptable patient-specific instruments can usefully expand the previous application areas. By using guided length adjustments, the fragments and optionally the graft can be compressed along a planned axis as desired to ensure optimal bone healing.Level of evidenceBasic science study, Surgical technique

Étude anatomique de l’insertion et de l’orientation des ligaments coraco-claviculaires : différence de positionnement des tunnels de reconstruction selon le sexe

BackgroundReconstructing both coracoclavicular ligaments following acromioclavicular dislocation has recently been reported to restore the function of the acromioclavicular joint better than traditional procedures. Knowing the appropriate position and orientation of the bone tunnels and the potential risks of neurovascular injuries leads to safe reconstruction. We aimed to answer the following questions: what is the difference in the accurate clavicular bone tunnel positions (BTPs) during coracoclavicular ligament reconstruction between sex, and what are the potential risks for neurovascular injuries? HypothesisThe BTPs differ by sex at the site of coracoclavicular ligament reconstruction. Patients and methodsWe introduced two Kirschner wires into 25 cadaver shoulders (17 male, 8 female), one through the insertion center of the trapezoid ligament and one through the conoid ligament, and measured the distance from the respective Kirschner wire insertion points to the bony landmarks of the clavicle and the oblique angle of each Kirschner wire. The shortest distance from the insertion point of each Kirschner wire to the suprascapular nerve and artery was also measured. ResultsWhile the distance from the acromioclavicular joint to the respective Kirschner wire insertion points tended to be longer in males, the ratio of these insertion points to total clavicle length was constant. Other measurements for respective Kirschner wire insertions to the bony landmarks and neurovascular structures were comparable, as were abduction and retroversion angles. The distance from the suprascapular nerve to the insertion point of the conoid ligament at the coracoid process was 13.8±4.0mm, while the distance from the suprascapular artery was 7.1±3.3mm. DiscussionAppropriate position and orientation of the bone tunnels, and the ratio of the BTPs to the total clavicular length, aid surgeons in performing the reconstruction. The conoid ligament insertion on the coracoid was just proximal to the suprascapular artery, so surgeons should be careful with conoid insertion. Level of evidenceV, cadaver study.

Structural effects of variation in the human clavicle.

Purported evolutionary shifts in shoulder structure have been linked to changes in hominin behavior and adaptation. Researchers use clavicle morphology to infer these shifts. However, there is a lack of empirical data underlying such predictive relationships. This study investigates how clavicle morphology affects articulated shoulder girdle and upper thorax configuration in humans. Landmarks and scalar measurements on the clavicle, scapula, and ribs 1-3 were collected from three-dimensional computed tomographic scans of living humans. Covariation between disarticulated and articulated morphology was assessed using partial least squares and regression analyses. We found support for hypotheses linking combined dimensions of the clavicle, ribs, and scapula to resting protraction. Individuals with relatively short clavicles tend to exhibit protracted and elevated resting positions of the scapula. It is more difficult to predict superoinferior configuration, which is only minimally affected by clavicle curvature. Instead, the superoinferior position of the scapula on the thorax is governed equally by clavicle orientation and rib declination. Shoulder breadth is determined primarily by clavicle length, but orientation has a comparable effect. Therefore, reliable reconstructions of shoulder breadth can be established using clavicle length, together with consideration of orientation. Relationships between clavicle and thorax morphology are weaker. Understanding the determinants of variation in human shoulder structure informs interpretation of skeletal remains. Our investigations describe how important aspects of shoulder structure can be inferred from disarticulated clavicles and we provide the attendant predictive equations. Future work on interspecific variation will improve skeletal reconstruction for more ancient hominins.

Minimally-invasive internal fixation for mid-lateral 1/3 clavicle fracture with distal clavicular anatomic locking plate

To investigate clinical effects of minimally-invasive internal fixation for mid-lateral 1/3 clavicle fracture with distal clavicular anatomic locking plate. From February 2016 to March 2017, 32 patients with mid-lateral 1/3 clavicle fractures treated by minimally-invasive internal fixation with distal clavicular anatomic locking plate, including 24 males and 8 females with an average of (42.3±12.7) years old (ranged from 22 to 68 years old). According to Robinson classification, 6 patients were type 2A2, 18 patients were type 2B1 and 8 patients were type 2B2. No vessel and nerve injury occurred before operation. The time from injury to operation ranged from 0 to 6 days with an average of (3.1±1.4) days. Length of bilateral clavicule were compared before and after operation to evaluate fracture reduction. Constant score at 6 months after operation was applied to assess recovery of shoulder function. Thirty patients were followed up from 11 to 18 months with an average of (13.3±2.2 ) months. No vessel and nerve injury, implant failure, nonunion or delayed union occurred after operation, and facture wound healed at stage I, the time ranged from 8 to 12 weeks with an average of(10.2±1.1) weeks. Shortened length of clavicle decreased from(11.2±3.6) % before operation to (0.4±0.3)% after operation at 2 days. Ten patients removed internal fixation at 8 months after operation without re-fracture occurred after remove plate. Constant score increased from 23.53±5.21 before operation to 94.30±5.60 after operation at 6 months, and 26 patients got excellent results, and 4 good. Patients were satisfied aesthetic degree of scar and shoulder joint function. Minimally-invasive internal fixation for mid-lateral 1/3 clavicle fracture with distal clavicular anatomic locking plate, which has advantages of less trauma, rapid recover, less scar, could receive good clinical effects and not effect beauty.

Why off-the-shelf clavicle plates rarely fit: anatomic analysis of the clavicle through statistical shape modeling

The clavicle presents a large variability in its characterizing sigmoid shape. Prominent and nonproperly fitting fixation plates (FP) cause soft tissue irritation and lead to hardware removal. It is therefore key in FP design to account for shape variations. Statistical shape models (SSMs) have been built to analyze a cluster of complex shapes. The goal of this study was to describe the anatomic variation of the clavicle using SSMs. Two different SSMs of the clavicle were created, and their modes of variation were described. One model contained 120 left male and female clavicles. The other model consisted of 76 left and corresponding right clavicles, 41 originating from men and 35 from women. The model of 120 left clavicles showed that 10 modes of variation are necessary to explain 95% of the variation. The most important modes of variation are the clavicle length, inferior-superior bow, and medial and lateral curvature. Statistically significant differences between male and female clavicles were seen in length, sigmoid shape, and medial curvature. Comparison in men between left and right revealed significant differences in length and medial curvature. For women, a statistically significant difference between left and right was only seen in the length. Although the operative treatment of displaced midshaft clavicular fractures has clear benefits, the variable anatomy of the clavicle often makes it challenging for the surgeon to make the plate fit adequately. Based on the identified variability in the clavicle's anatomy, it seems unlikely that a clavicle plating system can fit the entire population.

Anatomical study of the position and orientation of the coracoclavicular ligaments: Differences in bone tunnel position by gender

BackgroundReconstructing both coracoclavicular ligaments following acromioclavicular dislocation has recently been reported to restore the function of the acromioclavicular joint better than traditional procedures. Knowing the appropriate position and orientation of the bone tunnels and the potential risks of neurovascular injuries leads to safe reconstruction. We aimed to answer the following questions: what is the difference in the accurate clavicular bone tunnel positions (BTPs) during coracoclavicular ligament reconstruction between sex, and what are the potential risks for neurovascular injuries? HypothesisThe BTPs differ by sex at the site of coracoclavicular ligament reconstruction. Patients and methodsWe introduced two Kirschner wires into 25 cadaver shoulders (17 male, 8 female), one through the insertion center of the trapezoid ligament and one through the conoid ligament, and measured the distance from the respective Kirschner wire insertion points to the bony landmarks of the clavicle and the oblique angle of each Kirschner wire. The shortest distance from the insertion point of each Kirschner wire to the suprascapular nerve and artery was also measured. ResultsWhile the distance from the acromioclavicular joint to the respective Kirschner wire insertion points tended to be longer in males, the ratio of these insertion points to total clavicle length was constant. Other measurements for respective Kirschner wire insertions to the bony landmarks and neurovascular structures were comparable, as were abduction and retroversion angles. The distance from the suprascapular nerve to the insertion point of the conoid ligament at the coracoid process was 13.8±4.0mm, while the distance from the suprascapular artery was 7.1±3.3mm. DiscussionAppropriate position and orientation of the bone tunnels, and the ratio of the BTPs to the total clavicular length, aid surgeons in performing the reconstruction. The conoid ligament insertion on the coracoid was just proximal to the suprascapular artery, so surgeons should be careful with conoid insertion. Level of evidenceV, cadaver study.