When a dog is limping on one of their back legs, we often overlook the possibility of a paw injury and investigate injury to the larger joints of the hip or stifle. Paw injuries and strains however are quite common in dogs. Consider the strain caused if the dog’s toenail catches in the grass as they turn sharply, or an ache caused by having their foot accidently trod on.

When dogs injury their paws, they unload the affected limb to prevent further damage and to alleviate pain. Unloading the affected limb results in changes to the dog’s gait to compensate for reduced function.

Canine studies have shown that the nature of gait alterations may indicate the location of the loss of function i.e. hip, stifle, tarsus, or paw. Studies into gait alterations resulting from paw injuries however are limited hence the current study was designed to determine alterations to gait as a result of paw injuries specifically identifying alterations to limb, limb segment, and joint angles.

The study’s data collection was designed to:

• identify similarities and differences in kinematic adaptations to hindlimb lameness caused by proximal vs distal dysfunction i.e. hip or stifle vs paw
• test if dogs use similar strategies to unload a pelvic limb.

The study involved eight dogs trotting on a treadmill with force plates to record single limb ground reaction forces. Data was collected prior to and after an induced paw injury in the right hind limb. A recording session comprised five minute warmup and 15 trials each lasting 20 – 30 seconds, followed by a 15 minute break. After data was collected in the un-injured state, a small sphere was taped under the right paw to induce a lame state. A further recording session was conducted. On average, 11 trials were recorded in the lame condition.

Results

Gait alterations were observed in all limbs in the lame state. The affected limb showed the greatest gait alterations with changes to 30/59 parameters compared to the sound condition.

The contralateral (limb opposite the affect back leg) pelvic limb showed alterations to 25/59 parameters, followed by the contralateral thoracic limb (14/59) and finally, the ipsilateral thoracic limb (4/59).

In terms of changes in segment and joint angles detected, the mean degree of angular changes were greatest in the contralateral thoracic limb and least in the ipsilateral thoracic limb.

The contralateral pelvic limb protracted more resulting in increased joint angle at touch down, increased vertical position during mid-stance, and increased stance angular velocity.

By contrast, the affected limb was more retracted with increased angle at lift off.

The research also observed a vertical lowering of the hip and anteversion of the pelvis on touch down of the contralateral limb and ipsilateral limb on lift off.

Gait changes in the thoracic limbs

The most significant gait changes in the front legs was observed around the distal limb parts only. The contralateral carpal joint flexed more during the late stance and early swing phase due to reduced retroversion of the antebrachium (forearm) and anteversion of the lower leg.

On the ipsilateral limb, the antebrachium was retroverted more on touch down resulting in greater stance minimum. During the swing phase, reduced anteversion of the forearm was observed, resulting in greater range of motion.

Gait changes in the pelvic limbs

In the contralateral limb, the data indicated greater anteversion of pelvis, femur, lower leg, and foot through the entire gait. During the stance phase, the knee and tarsus joints were more flexed.

On the ipsilateral limb, the hip was more extended at lift off due to anteversion. The knee is more flexed in the mid-stance until the mid-swing phase. The tarsal joint extended more due to retroverted foot and the femur showed less retroversion during the swing phase.

Discussion

This study aimed to better understand the compensatory mechanisms that dogs adopt to cope with partial loss of function. Based as on this understanding, treatment plans can more accurately be designed to address both the site of injury or loss of function along with the joints and muscle groups that are overloaded as a result of the loss of function.

The key kinematic adaptions observed were as follows:

• The dog recruits the thoracic limb diagonally opposite the affected limb. Diagonal limbs exert forces in unison at the trotting gait thereby allowing thoracic limbs to compensate for loss of function in the pelvic limb.
• The dog engages the contralateral pelvic limb to cope with the loss of function. The ipsilateral thoracic limb is also affected for the same reason as above.

Canine massage treatment plan

From a soft tissue perspective, when a dog presents with an injured paw, then the treatment approach would likely be as follows:

• Ipsilateral forelimb – As this limb is the least affected by the altered gait, it is least likely to be sensitive to palpation. It is therefore ideal to start a treatment in this region. The focus of the treatment on this limb would be muscles in the neck, shoulder and forearm. Moving the joints of the limb through the full range of motion would assist in maintaining proprioception and relieve muscle strain.

• Contralateral forelimb – This limb bears much of the compensatory load, so the focus of a massage treatment would be on the muscle groups through the neck, shoulder, carpal and paw. Specifically, the carpal flexors would be treated due to the increased load on the carpal joint.

• Contralateral hindlimb – With the tilting of the pelvis in the altered gait, a massage treatment would focus on the gluteals, biceps, abdominal muscles, adductors, and hamstring muscles that originate at the pelvis. Additionally, treatment would focus on relieve strain in the muscle groups supporting the stifle and tarsus joints (gastrocnemius, sartorial, gracilis, cranial tibial, long peroneal) which are more flexed through the gait cycle.

• Affected hindlimb – With consideration for possible contraindications in this region, a treatment would aim to relieve strain in muscles engaging all joints of this limb. Additionally, treatment may involve range of motion and mobilisations to aid healing and proprioception in the injured paw.

The massage treatment plan would be tailored to each dog based on the diagnosis of the injury, contraindications and the dog’s level of tolerance to be treated.

Full Stride offers in home and clinic based canine massage treatments in Brisbane. For more information on injury prevention and paw related injuries please see:
https://www.fullstride.com.au/blog/dog-agility-jumping-problems-how-to-treat-to-a-foot-injury-in-a-dog

http://www.fullstride.com.au/blog/dog-is-limping

https://www.fullstride.com.au/blog/why-does-my-dog-hold-their-front-leg-up

Source:

Goldner, B, Fischer, S, Nolte, I and Schilling, N. (2018) “Kinematic adaptions to induced short term pelvic limb lameness in trotting dogs”. BMC Veterinary Research 14:183.