Question

As patient is walking, during the stance phase the knee goes into excessive hyperextension, then during deceleration part of swing phase, the knee snaps into extension. Most likely has:

a. gluteus medius gait
b. gluteus maximus gait
c. hamstrings weakness
d. quadriceps weakness

Answer 1

The patient's gait abnormalities, with knee hyperextension during walking, suggest quadriceps weakness. This is evident as the quadriceps cannot control the extension of the knee, leading to a 'snap' into hyperextension.

Step-by-step explanation:

When analyzing gait abnormalities in a patient, specific patterns can help determine underlying muscle weaknesses or pathologies. In this case, the patient's knee going into excessive hyperextension during the stance phase and the knee snapping into extension during the deceleration part of the swing phase suggests a weakness in the muscles responsible for knee control. Quadriceps weakness is the most likely cause of this condition because these muscles are primarily responsible for controlling knee extension.

The quadriceps, when weak, cannot adequately decelerate the leg during the swing phase, leading to a 'snap' into extension. Conversely, gluteus medius gait refers to a drop in the pelvis on the contralateral side when walking due to weakness in the gluteus medius muscle, and gluteus maximus gait is characterized by a backward lean of the trunk to compensate for weakness in the gluteus maximus. These patterns are not consistent with the knee hyperextension displayed by the patient. Hamstrings weakness typically results in inadequate knee flexion during the swing phase, not hyperextension. Thus, the description of the patient's symptoms best matches quadricpes weakness.