UPSC-CMS 2023 - Orthopaedics PYQs Practice Questions

Q: The following hallmarks characterise Diaphyseal aclasis except

Chondrosarcoma may occur in less than 1% cases. ***Chondrosarcoma may occur in less than 1% cases*** - This statement is incorrect as the risk of malignant transformation to **chondrosarcoma** in Diaphyseal aclasis (hereditary multiple exostoses) is commonly reported to be significantly higher, ranging from **5-25%**. - Therefore, stating it occurs in "less than 1% cases" is factually inaccurate, making this the correct answer as to what does *not* characterize the condition. *Pseudoarthrosis is common* - **Pseudoarthrosis** (false joint formation) can occur as a complication of **bony deformities** and the presence of osteochondromas, particularly in regions where they interfere with bone growth or cause fractures. - The abnormal growth of osteochondromas can predispose to fractures, which may heal poorly and result in pseudoarthrosis. *It is inherited as an autosomal dominant dysplasia* - Diaphyseal aclasis, also known as **hereditary multiple exostoses (HME)**, is indeed an **autosomal dominant** skeletal dysplasia. - It is caused by mutations in the **EXT1 or EXT2 genes**, which are involved in heparan sulfate proteoglycan synthesis, leading to abnormal bone growth. *Genu valgum can be found* - **Genu valgum** (knock-knees) is a common **skeletal deformity** observed in individuals with Diaphyseal aclasis. - The multiple osteochondromas can disturb the normal growth and alignment of long bones, frequently affecting the distal femur and proximal tibia leading to this angular deformity. [Practice more Orthopaedics PYQs on OnCourse]

Q: Consider the following clinical features : 1. Low back pain 2. Saddle anaesthesia 3. Motor weakness in the lower extremities 4. Variable rectal and urinary symptoms Which of the above features may be present in a patient with Cauda Equina syndrome ?

1, 2, 3 and 4. ***1, 2, 3 and 4*** - **Cauda equina syndrome** is a serious neurological condition involving compression of the cauda equina nerve roots, typically manifesting with **low back pain**, **saddle anesthesia**, and **motor weakness** in the lower extremities [1]. - The compression of the nerve roots can also lead to varying degrees of **rectal and urinary dysfunction**, including incontinence or retention, depending on which nerve roots are affected [2]. *1, 2 and 3 only* - While **low back pain**, **saddle anesthesia**, and **motor weakness** are prominent features of cauda equina syndrome, this option incorrectly excludes the crucial symptom of **rectal and urinary dysfunction**. - **Bladder and bowel dysfunction**, along with sexual dysfunction, are hallmark symptoms resulting from the involvement of sacral nerve roots in cauda equina compression [2]. *1 and 2 only* - This option correctly identifies **low back pain** and **saddle anesthesia** as features but omits two critical components of cauda equina syndrome: **motor weakness** and **rectal/urinary symptoms** [1]. - Without considering **motor weakness** and **sphincter dysfunction**, the diagnostic picture of cauda equina syndrome is incomplete, potentially delaying necessary surgical intervention [3]. *3 and 4 only* - This option incorrectly suggests that **motor weakness** and **rectal/urinary symptoms** are the only relevant features, excluding the highly characteristic **low back pain** and **saddle anesthesia**. - **Low back pain** is almost universally present and **saddle anesthesia** is a key indicator of sacral nerve root involvement, crucial for distinguishing cauda equina syndrome from other neurological conditions [1]. [Practice more Orthopaedics PYQs on OnCourse]

Question 1

The following hallmarks characterise Diaphyseal aclasis except

Accepted Answer

Chondrosarcoma may occur in less than 1% cases

Answer

Pseudoarthrosis is common

Answer

It is inherited as an autosomal dominant dysplasia

Answer

Genu valgum can be found

Question 2

Consider the following clinical features :

1. Low back pain
2. Saddle anaesthesia
3. Motor weakness in the lower extremities
4. Variable rectal and urinary symptoms Which of the above features may be present in a patient with Cauda Equina syndrome ?

Accepted Answer

1, 2, 3 and 4

Answer

1, 2 and 3 only

Answer

1 and 2 only

Answer

3 and 4 only

UPSC-CMS 2023 — Orthopaedics