While examining his knee jerk Suresh's doctor found that there was no response but Suresh informs that he could feel the tendon hammer touching his knee. Where is the problem likely to be ?

Options

A. Afferent pathway
B. Dorsal ganglion
C. Receptors
D. Efferent pathway

Answer

To solve the problem presented in the question, we need to analyze the components of the knee jerk reflex and identify where the issue lies based on the information provided.

### Step-by-Step Solution:

1. **Understanding the Knee Jerk Reflex**:
- The knee jerk reflex is a simple reflex action that involves several components: receptors, afferent pathways, the central nervous system (CNS), efferent pathways, and effectors (muscles).

2. **Identifying the Components**:
- **Receptors**: These are sensory receptors in the muscle (e.g., muscle spindle) that detect the stretch when the tendon hammer hits the knee.
- **Afferent Pathway**: This pathway consists of sensory neurons that carry the signal from the receptors to the spinal cord.
- **Central Nervous System**: The spinal cord processes the information received from the afferent pathway.
- **Efferent Pathway**: This pathway consists of motor neurons that carry the response signal from the spinal cord back to the muscle.
- **Effectors**: The muscles that respond to the signal (in this case, the quadriceps muscle).

3. **Analyzing Suresh's Condition**:
- Suresh reports that he can feel the tendon hammer touching his knee, indicating that the sensory receptors and the afferent pathway are functioning properly.
- However, there is no knee jerk response, which suggests that the reflex arc is not completing properly.

4. **Locating the Problem**:
- Since Suresh can feel the touch, the issue is not with the receptors or the afferent pathway.
- The problem is likely located in the central nervous system (specifically the spinal cord) or the efferent pathway that leads to the muscle.
- Given that the knee jerk reflex is not occurring, the issue is likely with the efferent pathway or the motor neurons.

5. **Conclusion**:
- The most probable location of the problem is in the dorsal ganglion or the motor neurons, which are part of the efferent pathway. This means that the signals from the spinal cord to the muscle are not being transmitted effectively, leading to the absence of the reflex response.

### Final Answer:
The problem is likely to be in the **efferent pathway** (motor neurons) or the **dorsal ganglion**.