ABOS Part I Comprehensive Review - Batch 74

Question 1

A 32-year-old carpenter presents with progressive difficulty making a full fist with his right ring finger, particularly when attempting to grasp small objects. He reports a history of a 'Jersey finger' injury to the same digit 6 months prior, which

Accepted Answer

Proximal retraction of the avulsed FDP tendon, causing the lumbrical to become functionally unopposed distally.

Question 2

A 28-year-old concert pianist develops a lumbrical plus deformity in her left index finger following a flexor tendon repair. She is concerned about the impact on her career. A thorough understanding of the lumbrical muscles is crucial for her surgeon

Accepted Answer

The first and second lumbricals are unipennate and innervated by the median nerve, while the third and fourth are bipennate and innervated by the ulnar nerve.

Question 3

A 55-year-old patient presents with a lumbrical plus deformity of the middle finger following a complex flexor tendon reconstruction. The surgeon explains that the deformity results from a disruption of normal force transmission. Which of the followi

Accepted Answer

Excessive tension on the FDP tendon restricts its distal excursion, causing the contracting FDP to pull predominantly on the lumbrical origin, leading to paradoxical IP extension.

Question 4

A 40-year-old patient presents with a lumbrical plus deformity of the ring finger, significantly impacting her ability to perform daily tasks. After a trial of hand therapy, the deformity persists. The surgeon is considering surgical intervention. Ac

Accepted Answer

Active infection in the surgical field.

Question 5

A 60-year-old patient is scheduled for surgical correction of a lumbrical plus deformity in the small finger. During pre-operative planning, the surgeon emphasizes the importance of a detailed history and physical examination. Which of the following

Accepted Answer

Paradoxical extension of the PIP and DIP joints during attempted active flexion of the digit.

Question 6

A 48-year-old patient is undergoing surgical correction for a lumbrical plus deformity of the middle finger. The surgeon has made a Brunner zig-zag incision and meticulously protected the digital neurovascular bundles. After exposing the flexor sheat

Accepted Answer

It originates from the radial side of the FDP tendon in the palm, distal to the carpometacarpal joint line, appearing as a reddish-brown muscle belly transitioning into a thin tendon.

Question 7

A 35-year-old patient undergoes a lumbrical tenotomy for a lumbrical plus deformity of the ring finger. During the immediate post-operative period (Day 0-7), the hand therapist applies a dorsal blocking splint. Which of the following positions is typ

Accepted Answer

Wrist in slight flexion, MCP joints in moderate flexion (70-90 degrees), IP joints in full extension; to prevent MCP flexion contractures and facilitate IP flexion.

Question 8

A 50-year-old patient presents with a recurrent lumbrical plus deformity after a previous lumbrical tenotomy. Intraoperative assessment confirms significant over-tensioning of the flexor digitorum profundus (FDP) tendon as the primary underlying caus

Accepted Answer

FDP lengthening is typically performed via a Z-plasty in the mid-palmar or forearm region, aiming to achieve appropriate tension without causing a quadriga effect.

Question 9

A 22-year-old athlete undergoes surgical correction of a lumbrical plus deformity. Post-operatively, he develops persistent, disproportionate pain, swelling, skin color changes, and allodynia in the affected hand. These symptoms are suggestive of Com

Accepted Answer

Multimodal pain management, aggressive hand therapy focusing on desensitization, and psychological support.

Question 10

A 42-year-old patient is recovering from a lumbrical tenotomy for a lumbrical plus deformity. During Phase II (Weeks 1-3) of rehabilitation, the hand therapist initiates several interventions. Which of the following is a key component of rehabilitati

Accepted Answer

Initiation of gentle, active flexion and extension exercises for the affected MCP, PIP, and DIP joints, focusing on isolated FDP and FDS gliding.

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Key Takeaway