Incidence of long bone fractures in dogs
A total of 21,719 clinical cases of dogs were presented to the surgery ward of SVVU Super Speciality Veterinary Hospital, Visakhapatnam from February 2017 to 2020. Of these 438 (2.02%) cases were diagnosed to have fracture of different bones and among them, 326 had fracture of long bones, comprising 1.50% of total cases and 74.42% of fractures cases presented.
Breed wise distribution
Long bone fractures were recorded in sixteen different breeds (Table 1). The highest incidence was recorded in Mongrel/ non-descriptive dogs (n=129, 39.57%) followed by Pomeranian (n=74, 22.70%), mixed breed (n=37, 11.35%), Labrador retriever (n=19, 5.83%), German Shepherd (n=11, 3.37%), Golden retriever (n=9, 2.76%) and 2.15% (n=7) each in Dobermann pinscher, Dachshund, Lhasa Apso and least incidence in Tibetan mastiff (n=1, 0.31%).
Age wise distribution
Highest incidence was observed in the dogs of juvenile age group (n=129, 39.57) followed by mature adult (n=71, 21.78%), young adult (n=68, 20.86%) and geriatric dogs (58, 17.79%).
Sex wise distribution
Higher incidence was recorded in males (n=184, 56.44%) than that in females (n-142, 43.44%).
Limb wise distribution
Highest incidence was noticed in left hind limb (n=126, 38.41%) followed by right hind limb (n=87, 26.52%), right fore limb (n=63, 19.21%) and left fore limb (n=52, 15.85%). In two dogs bilateral limb fractures were recorded. In the present study incidence of fracture was higher in hind limbs (n=213) when compared to that in fore limbs (n=115).
Bone- wise distribution
Highest incidence of fractures was recorded in tibia and fibula (n=126, 38.07%) followed by radius and ulna (n=97, 29.32%), femur (n=89, 26.89%) and humerus (n=19, 5.74%).
Distribution of long one fractures based on etiological factors
Fall from a height (n=141, 43.25%) was recorded as most common etiological factor responsible for long bone fractures followed by automobile accidents (n=118, 36.20%), unknown etiology (n=31, 9.51%), trauma by inanimate objects in the surroundings (n=27, 8.28%), dog bite (n=7, 2.15%) and pig bite (n=2, 0.61%).
Classification of fractures based on radiographic signs
All the dogs with non-weight bearing lameness were subjected to radiography to identify the location and type of fracture. Forty eight out of 326 dogs needed sedation for this procedure. Based on these radiographic findings, the fractures were categorized as shown in the Table 2. Out of all type of fractures, complete diaphyseal long oblique fractures are reported more in humerus bone (n=6), complete diaphyseal transverse fractures are reported more in radius ulna bone (n=56), complete diaphyseal long oblique fractures are reported more in femur bone (n=23) and complete diaphyseal short oblique fractures are reported more in tibia fibula bone (n=59). The percentage of complete short oblique diaphyseal fractures was found to be high among all the cases where as avulsion and segmental fractures found to be low. Avulsion fractures were noticed only in tibia fibula bone (n=5). Salter Harris fracture were noticed more in the femur bone (n=16) when compared to other bones in the present study.
During this study an overall incidence of fractures in dogs was recorded 2.1% with long bone fractures comprising 74.42% of all fractures cases. These obervations fall in line with those of
Patil et al., (2018) who also reported 2.48% overall incidence of long bone fractures in canines. However, higher overall incidence of fractures 7.33%
(Kushwaha et al., (2011) and 17.8%
Ali (2013) have also been reported.
In the present study, the long bone fractures were recorded in sixteen dog breeds among which the prevalence was highest in mongrel/non-decriptive and the lowest in Tibetan Mastiff. Similar to the present study, the higher incidence of fractures in non-descriptive breed was also reported by
Dvorak et al., (2000), Rani et al., (2007), Simon et al., (2011), Manjunatha and Ranganath (2012),
Patil et al., (2018) and
Priyanka et al., (2019). Highest incidence was reported in other breeds too like Spitz
(Aithal et al., 2004, Kumar et al., 2007 and
Kushwaha et al., 2011), Mixed breed
(Libardoni et al., 2016), German Shepherd
(Balagopalan et al., 1995 and
Jani et al., 2014), Labrador retriever
(Priyanka et al., 2019) and Yorkshire terrier
(Minar et al., 2013). Highest prevalence recorded in non-descriptive breeds could be attributed to their increased geographical distribution
(Simon et al., (2011), Manjunatha and Ranganath, (2012) and
Gill et al., (2018).
Highest incidence of long bone fractures was recorded in the dogs of Juvenile group and lowest incidence in geriatric group. Our findings are in accordance with those of
Phillips (1979),
Balagopalan et al., (1995), Aithal et al., (2004), Raghunath et al., (2007), Rani et al., (2007), Simon et al., (2010; 2011),
Kushwaha et al., (2011) and
Minar et al., (2013), who also reported the highest incidence of long bone fractures in the dogs aged less than one year. The higher susceptibility of young dogs to the fractures could be attributed to their soft, low density and fragile bones that are in the phase of osteogenesis and being likely to get injured even by a minor trauma
(Shapiro, 2008 and
Minar et al., 2013). Moreover the inability of the young dogs to avoid trauma make them prone fractures
(Vidane et al., 2014).
Finding of the present study male dogs appeared more susceptible for the long bone fractures than the female dogs is in concomitance with those of other researchers
Alcantara and Stead (1975),
Phillips (1979),
Balagopalan et al., (1995), Aithal et al., (1999), Dvorak et al., (2000), Fazili et al. (2005),
Kumar et al., (2007), Simon et al., (2011), Jani et al. (2014),
Libardoni et al., (2016), Patil et al., (2018) and
Priyanka et al., (2019). Increased male susceptibility to long bone frcatures might be due to their increased metabolic activity than females
(Kumar et al., 2007 and
Aithal et al., 1999), aggressive behaviour
(Fazili et al., 2005) and wandering nature
(Raouf et al., 2017 and
Libardoni et al., 2016). And more population of male dogs
(Patil et al., 2018) as the people prefer to rear male dogs as companion animals compared to female dogs Contrarily
Altunatmaz et al., (2012) reported higher incidence of fractures in female dogs without stating any reason.
Hind limbs appeared more susceptible as compared to fore limbs; and left limbs appeared more susceptible when compared to right limbs. These observations are in total consonance with those of
Balagopalan et al., (1995), Rhangani, (2014) and
Bennour et al., (2014), who reported higher incidence of fractures in hind limbs and with those of
Alcantara and Stead, (1975),
Aithal et al., (2004) and
Raghunath et al., (2007) who also reported that left sided limbs were more susceptible to fractures as compared to right.
Singh et al., (1983) attributed this more incidence of fractures in hind limbs to slower reaction of dogs at their hind limbs during an effort to flee away from the impending trauma and exposing the hind quarters to trauma.
Harasen (2003) stated that, trauma to the caudal half of the animals was less likely to produce life threatening injury and such type of animals were more frequently presented to the hospitals for treatment. Contrararily
(Rani et al., 2007) recorded highest occurance of fractures in right side limbs.
Tibia-fibula was observed as the most affected bone followed by radius ulna, femur and humerus in the present study. The findings are in contrast with those of
Maala and Celo (1975),
Philips (1979),
Balagopalan et al., (1995), Harasen (2003),
Ozsoy (2004),
Raghunath et al., (2007), Simon et al., (2010), Kushwaha et al., (2011), Altunatmaz et al., (2012), Vidane et al., (2014) and
Patil et al., (2018) who reported the highest incidence of fractures in femur bone.
Dvorak et al., (2000) reported the higher incidence of fractures in radius ulna. Weight bearing stress, in addition to normal anatomical position with geometric variation in the length of bone make the femur more vulnerable to fractures
(Markel et al., 1994).
In the present study, the common etiological factor responsible for long bone fractures reported was fall from a height followed by automobile accidents. The findings were in accordance with those of
Aithal et al., (2004), Kushwaha et al., (2011) and
Raouf et al., (2017). Several researchers like
Alcantara and Stead (1975),
Phillips (1979),
Ozsoy (2004),
Rani et al., (2007), Altunatmaz et al., (2012), Ali (2013),
Libardoni et al., (2016) and
Priyanka et al., (2019) reported Automobile accidents/traffic accidents as a principal cause of long bone fractures in dogs. However
Rhangani (2014) reported, unknown trauma as a principal cause of fractures in their study.
Alcantara and Stead (1975),
Rhangani (2014) and
Libardoni et al., (2016) also reported animal bites as one of the causes for fractures in dogs similar to our study.
Non-weight bearing lameness on the affected limb, abnormal angulation of limb at the site of fracture, swelling at the site of fracture, crepitation at site of fracture and pain on palpation were the common symptoms noticed in the present study as reported by
Kumar et al., (2007), Bennour et al. (2014),
Madhu et al., (2014), Patil et al., (2017) and
Chaurasia et al., (2019) in the animals suffering with fractures.
Complete diaphyseal short oblique fracture was the commonest type of fracture noticed in majority cases followed by complete diaphyseal transverse fracture and complete diaphyseal long oblique fracture. The present findings differ with the observations of
Shiju et al., (2010; and 2011); Ali, (2013),
Jain et al., (2016) who observed more transverse fractures followed by oblique fractures. Higher incidence of transverse and oblique fractures in the present study might be due to predominance of bending forces at the site of fracture. Similar opinion was also made by
Smith, (1985). In the present study, avulsion fracture was noticed only in tibia which could be due to incomplete fusion of tibial tuberosity to the rest of bone in young animals. Similar opinion was also made by
Shiju et al., (2010).
