The scapulae with type III suprascapular notch (SSN) were the most prevalent in our study (51%) and the prevalence of complete ossification of the superior transverse scapular ligament (STSL; type VI SSN) was moderately high (8.2%). These findings concur with those from previous studies in the American, Greek, Kenyan, Polish, Italian, and Indian populations where the values were 22.8–56.2% and 0–10% for types III and VI respectively, Table 1 [4, 7, 9, 11, 14,15,16]. There are dynamic statistics regarding the prevalence of complete ossification of STSL in the current study among the Ugandan population in comparison to other populations i.e. twice the mean prevalence of the previous studies among multiple populations (4%), eight times more than in the Greek population (0%), about twice that of American (4%), Italian (3.6) and Kenyan (3%) populations, and similar to that of the Polish (7%) and Indian (10%) populations Table 1 [4, 7, 9, 11, 14,15,16]. But despite the above variability regarding the prevalence of the completely ossified STSL in the Ugandan population, the prevalence of completely ossified STSL in our study (8.2%) falls within the range of the previous data in other populations (0–10%) [4, 7, 9, 11, 14,15,16] and has been cited as one of the major risk factors associated with the suprascapular neuropathy due to SN entrapment [4, 6,7,8, 14, 15].
The scapulae with completely ossified STSLs (type VI) of our study could not be differentiated from other SSN types using the basic morphometric scapular dimensions (A, B, C, and D) i.e. the dimensions were statistically similar for all the SSN types, except for type IV SSN. Our findings concur with previous findings that showed no significant differences between the scapular dimensions of different SSN types [9, 16]. This is an indication that the morphological dimensions of the scapular body and glenoid fossa are not straight-forward predictors of the occurrence of SN entrapment syndrome from complete ossification of the STSL associated with type VI SSN. It is worthy to note that types VI and IV SSN had statistically different morphological lengths of the scapular body (A) and glenoid fossa (C), this finding could be exploited in medicine in the prediction, diagnosis, and assessment of the SN Entrapment syndrome caused by either type IV or VI but because previous studies have shown both types as being associated with SN Entrapment syndrome , and because scapular width (B) and glenoid width (D) were similar for the two types, this finding is of less clinical value about SN neuropathy. Furthermore, our study has shown that based on the morphological dimensions of scapulae (A, B, C, and D), it is generally not possible to differentiate scapulae of type III and IV from those with type I and II SSNs as all have similar scapular dimensions. Because people with a type IV and III SSNs are more predisposed to the SN entrapment syndrome than those with type I and II [7, 13, 15, 16], the study seems to suggest that our dimensions are of less value in the prediction of occurrence, proper diagnosis, and assessment of the SN entrapment syndrome associated with types III and IV SSN, and although our study established significantly different scapular body lengths between types II, III, and IV this finding needs further exploration before we can conclude it as being useful in differentiating scapulae with type II SSN from those associated with predisposition to SN neuropathy (type III and IV).
For all SSN types in general, there is a strong direct connection between A and B axis; the more A increases, the greater the B axis via an exact linear rule, this finding was in tandem with Polguj et al.  where the maximal depth (MD) of the SSN correlated with the morphological length of the scapulae . However, most other morphometric measurements in this population indicate a moderate positive linear relationship via a fuzzy-firm linear rule, indicating that it is not very easy to use these relationships to predict the status of these dimensions in the population and that the patient’s scapular dimensions were not related to the characteristics of the SSN such as shape and type of the SSN , a picture similar to the study by Polguj et al.  where most of the other correlation relationships such as the moderate negative correlation (weak correlations) between the maximal depth (MD) of the SSN and scapular width-length index (WLI) were obtained . In general, the patient’s scapular dimensions were not related to the characteristic of the SSN (type of SSN) and thus the scapular dimensions are not necessary predictors of type of SSN in a given scapula and vice versa.
Considering all the six types of SSN in our study, scapulae with SSN types I, III, and IV have direct relationships between scapular dimensions A, B, C, and D; as one of these dimensions increases, the others also increase linearly. However, this linear relationship is only observed between scapular axes A and B of type VI and concurs with Polguj et al.  where a positive correlation between the maximal depth (MD) and the morphological length of the scapulae was seen. The rest of the correlations related to dimensions of SSN type VI are either strongly (A and D; B and D) or weakly negative indicating an inverse correlation also consistent with Polguj et al. who found a negative correlation between the maximal depth (MD) of the SSN and scapular width-length index . This indicates that for type VI SSN, as the A and B axes increases, the D axis tends to decrease through an exact linear rule. This finding indicates that the relationship between scapular dimensions A, B against D can be exploited to find scapulae with SSN type VI and therefore can be exploited for the possible prediction of SN entrapment syndrome associated with it. There are strong (positive or negative) correlations between types I and III from type VI for A-axis; types I, III from VI for B; type IV and VI for the C axis; and type III and VI for the D axis. From the above findings it can be concluded that correlations from all the four morphological lengths of the scapulae (A, B, C, and D): are strong and statistically significant, and therefore can be used to differentiate types I and III from type VI using the A axis B axis can identify types I, III from VI; C axis can be used to identify type IV from VI, and D axis can be used to identify type III from type VI SSN. These correlations show that correlation studies regarding scapular morphological dimensions (scapular length and width; glenoid length and width) are strong and statistically significant in agreement with Polguj et al.  but in contradiction with Albino et al.  that got weak correlation indices. The strong correlations obtained in our study could be of clinical value in the prediction, diagnosis, and assessment of SN entrapment syndrome associated with type VI SSN as suggested by Polguj et al.  using the correlation between maximal depth of the scapular notch with the morphological length of the scapulae .
In general, the correlation analyses of our study have shown that the scapular dimensions (scapular length and width; glenoid length and width) might be of value in the diagnosis, assessment, and prevention of SN entrapment syndrome associated with scapulae of type III, IV and VI SSN emphasizing the clinical significance of scapular dimensions in helping clinicians, radiologists, and orthopedic surgeons perform better with minimal complications in agreement with previous findings [1,2,3].
The current study had some limitations: it did not focus on the gender and age-related differences associated with the morphometric correlation analyses of the scapula, and it employed a low number of specimens for the correlation analyses. In the future, a prospective study will be conducted using a robust sample size to analyze the gender and age-related differences associated with the correlation analyses of scapular dimensions of different SSN types.