Free Orthopedic Surgery mock test

Orthopedic Surgery sample questions with answers

10 more original exam-style Orthopedic Surgery questions, worked in full. They are not real or recalled exam questions, and none of them is in the mock above or on the bank page, so sit the mock first if you have not.

1. Question 1 · Pediatric Orthopedics

   A 4-month-old infant has been treated in a Pavlik harness for a dislocated but reducible left hip. After three weeks of full-time harness wear, ultrasound shows the femoral head remains posteriorly dislocated and there is early flattening of the posterior acetabular wall. What is the most appropriate next step?

   1. AContinue the harness for a further six weeks and repeat the ultrasound
   2. BIncrease hip flexion in the harness beyond 110 degrees to force reduction
   3. CDiscontinue the harness and proceed to closed reduction under anaesthesia with arthrogram and spica cast
   4. DProceed directly to open reduction with Salter innominate osteotomy
   Show answer and explanation

   Correct answer: C. Discontinue the harness and proceed to closed reduction under anaesthesia with arthrogram and spica cast

   A hip that has not reduced after about three weeks of appropriate Pavlik harness use should have the harness abandoned, since continued wear against a dislocated head erodes the posterior acetabular wall and causes Pavlik harness disease, making later reduction harder. The correct next step is examination under anaesthesia with arthrography and closed reduction, adductor tenotomy if needed, and spica immobilisation, with open reduction reserved for failure of closed reduction. Excessive flexion does not achieve reduction and risks femoral nerve palsy, and pelvic osteotomy is not indicated at 4 months of age before an attempt at closed reduction.

   Reference: AAOS Clinical Practice Guideline on DDH (2014); Tachdjian's Pediatric Orthopaedics, 6th edition, 2021

2. Question 2 · Spine

   A 58-year-old man has degenerative cervical myelopathy with compression at C4-C5, C5-C6 and C6-C7. Standing radiographs show a kyphotic cervical alignment with a C2-C7 Cobb angle of 12 degrees of kyphosis. Which surgical strategy is most appropriate?

   1. AOpen-door laminoplasty from C3 to C7
   2. BAnterior decompression (multilevel discectomy or corpectomy) with fusion to restore lordosis
   3. CPosterior laminectomy alone from C3 to C7 without instrumentation
   4. DPosterior foraminotomies at the three affected levels
   Show answer and explanation

   Correct answer: B. Anterior decompression (multilevel discectomy or corpectomy) with fusion to restore lordosis

   Laminoplasty and posterior decompression rely on the cord drifting backwards away from anterior osteophytes and discs, which only occurs when the cervical spine is lordotic; in a kyphotic spine the cord remains draped over the anterior pathology, so an anterior decompression and fusion that also corrects alignment is preferred. Laminectomy without instrumentation additionally risks progressive post-laminectomy kyphosis and late deterioration. Foraminotomy addresses radiculopathy from foraminal stenosis and does not decompress the central canal.

   Reference: Fehlings MG et al., Global Spine Journal (2017); Rothman-Simeone and Herkowitz The Spine, 7th edition (2018)

3. Question 3 · Patient Safety, Professionalism, Ethics & Evidence-Based Practice

   An orthopedic department in the UAE wishes to upload de-identifiable imaging and outcome data for an arthroplasty study to a cloud server physically located outside the country. Which statement best reflects the regulatory position?

   1. AHealth data generated inside the UAE may not be stored, processed or transferred outside the State unless an exception is permitted and authorisation is obtained from the relevant health authority
   2. BTransfer is unrestricted provided the data have had names removed
   3. CTransfer is permitted as long as the cloud provider is internationally accredited
   4. DOnly genetic data are subject to cross-border restriction; imaging and outcome data are exempt
   Show answer and explanation

   Correct answer: A. Health data generated inside the UAE may not be stored, processed or transferred outside the State unless an exception is permitted and authorisation is obtained from the relevant health authority

   UAE Federal Law No. 2 of 2019 on the Use of Information and Communication Technology in Health Fields requires that health data generated within the State be stored and processed inside the UAE, with transfer abroad permitted only under defined exceptions and with authorisation from the relevant health authority. Removing names or using an accredited foreign vendor does not by itself satisfy this data-localisation requirement. The restriction applies to health information broadly, not solely to genetic data.

   Reference: UAE Federal Law No. 2 of 2019 concerning the Use of Information and Communication Technology in Health Fields; UAE Federal Decree-Law No. 45 of 2021 on Personal Data Protection

4. Question 4 · Musculoskeletal Infection

   An orthopedic department wants to benchmark its deep surgical site infection rate after hip arthroplasty against national data. Which approach best reflects sound surveillance methodology?

   1. AProspective surveillance using standardised case definitions with a defined post-discharge follow-up period, reported with risk adjustment
   2. BCounting only infections identified before discharge, since post-discharge cases are unrelated to surgery
   3. CReporting the crude number of infections per year without a denominator of procedures
   4. DRelying on the surgeons' recollection of complications at the annual audit meeting
   Show answer and explanation

   Correct answer: A. Prospective surveillance using standardised case definitions with a defined post-discharge follow-up period, reported with risk adjustment

   Meaningful benchmarking requires prospective surveillance with standardised definitions (for example, CDC/NHSN superficial, deep incisional and organ/space categories), consistent post-discharge follow-up because most deep implant infections present after discharge, a procedure denominator, and risk adjustment for case mix. Inpatient-only ascertainment systematically underestimates the rate, raw counts without denominators are uninterpretable, and retrospective recall is subject to major bias.

   Reference: CDC/NHSN Surgical Site Infection Event surveillance definitions (2023); WHO Global Guidelines for the Prevention of Surgical Site Infection (2nd ed., 2018)

5. Question 5 · Metabolic Bone Disease & Systemic Skeletal Disorders

   A 48-year-old man on haemodialysis for nine years presents with a pathological fracture through an expansile lytic lesion of the proximal femur. Biopsy shows multinucleated giant cells in a haemorrhagic fibrous stroma with haemosiderin. Calcium is 2.75 mmol/L and PTH is 1400 pg/mL despite a functioning transplant assessment. What is the definitive management of the underlying disease?

   1. AWide resection and endoprosthetic replacement for giant cell tumour
   2. BDenosumab monotherapy
   3. CParathyroidectomy for tertiary hyperparathyroidism, with stabilisation of the fracture
   4. DRadiotherapy to the femoral lesion
   Show answer and explanation

   Correct answer: C. Parathyroidectomy for tertiary hyperparathyroidism, with stabilisation of the fracture

   The histology describes a brown tumour, a reparative giant-cell lesion of hyperparathyroidism, and autonomous PTH secretion with hypercalcaemia after long-standing renal failure is tertiary hyperparathyroidism; parathyroidectomy corrects the driver and brown tumours typically regress and remineralise. Although histologically similar to giant cell tumour, the biochemical context makes oncological resection inappropriate. Denosumab does not address autonomous PTH secretion and risks severe hypocalcaemia in renal failure, and radiotherapy has no role and carries malignancy risk.

   Reference: KDIGO Clinical Practice Guideline Update for CKD-MBD (2017); Miller & Brinker Review of Orthopaedics, 8th ed. (2020)

6. Question 6 · Orthopedic Trauma - Adult Fractures, Dislocations & Polytrauma

   A 30-year-old sustains a posterior wall acetabular fracture with an associated posterior hip dislocation, reduced in the emergency department. Post-reduction CT shows a posterior wall fragment involving approximately 45% of the wall, and the hip is congruent. Which factor most strongly supports operative fixation?

   1. AThe presence of an ipsilateral femoral shaft fracture
   2. BThe wall fragment size, which predicts instability with fragments involving more than about 40-50% of the posterior wall
   3. CThe presence of a sciatic nerve palsy, which is an absolute indication for fixation
   4. DThe age of the patient being under 40 years
   Show answer and explanation

   Correct answer: B. The wall fragment size, which predicts instability with fragments involving more than about 40-50% of the posterior wall

   Biomechanical and clinical studies show that posterior wall fragments involving more than roughly 40-50% of the wall are almost always unstable and require open reduction and internal fixation, whereas fragments under 20% are usually stable; intermediate sizes are assessed with an examination under anaesthesia. A sciatic nerve palsy warrants urgent reduction and exploration in selected cases but is not by itself the determinant of wall fixation, an ipsilateral femoral fracture affects sequencing rather than the acetabular indication, and age alone is not the criterion.

   Reference: Moed BR et al., posterior wall acetabular fracture stability and EUA; Tornetta P III, Rockwood and Green's Fractures in Adults, 9th edition (2020)

7. Question 7 · Basic Science & Principles of Orthopedics

   A circular fine-wire frame applied to the tibia is judged insufficiently stiff. Which modification would most increase the stability of the construct?

   1. AUse rings of smaller diameter that sit closer to the limb
   2. BReduce the tension applied to the transfixion wires
   3. CIncrease the distance between the rings and the fracture site
   4. DArrange the crossing wires at an angle of about 20 degrees to each other
   Show answer and explanation

   Correct answer: A. Use rings of smaller diameter that sit closer to the limb

   Frame stiffness increases with smaller ring diameter (roughly two fingerbreadths of clearance), higher wire tension (about 130 N for a 1.8 mm wire), larger-diameter wires, more wires per ring, wires crossing closer to 90 degrees, and rings placed close to the fracture. Reducing wire tension, increasing ring-to-fracture distance and acute crossing angles all reduce stability, particularly in shear and bending.

   Reference: Campbell's Operative Orthopaedics, 14th edition (2021); Miller's Review of Orthopaedics, 8th edition (2020)

8. Question 8 · Perioperative Care, Rehabilitation & Complications

   Six months after ACL reconstruction, a patient has a 12-degree fixed flexion deformity, painful terminal extension and a palpable nodule anterior to the tibial tunnel on MRI. Which is the most likely diagnosis and appropriate treatment?

   1. ACyclops lesion (localised anterior arthrofibrosis) treated by arthroscopic excision and restoration of extension
   2. BGraft rupture requiring immediate revision reconstruction
   3. CSeptic arthritis requiring arthroscopic washout and prolonged antibiotics
   4. DPatellar tendinopathy managed with eccentric loading alone
   Show answer and explanation

   Correct answer: A. Cyclops lesion (localised anterior arthrofibrosis) treated by arthroscopic excision and restoration of extension

   A cyclops lesion is a focal fibroproliferative nodule anterior to the graft at the tibial tunnel that blocks terminal extension and produces a painful, springy extension block; arthroscopic debridement reliably restores extension. Graft rupture presents with instability and a positive Lachman/pivot shift, not a fixed extension block. Septic arthritis would cause effusion, warmth, pain and raised inflammatory markers, usually much earlier. Patellar tendinopathy causes anterior knee pain with loading but does not create a mechanical extension block or a nodule in the notch.

   Reference: DeLee, Drez and Miller's Orthopaedic Sports Medicine, 5th edition (2020); Jackson and Schaefer, Cyclops syndrome, Arthroscopy 1990

9. Question 9 · Orthopedic Sports Medicine & Arthroscopy

   A 54-year-old manual worker has a massive irreparable posterosuperior rotator cuff tear with Hamada grade 1 changes, no glenohumeral arthritis, a functioning deltoid and an intact subscapularis. Pseudoparalysis is absent. Which option best preserves the joint while restoring superior stability?

   1. AArthroscopic superior capsular reconstruction
   2. BReverse total shoulder arthroplasty
   3. CIsolated subacromial decompression with acromioplasty
   4. DGlenohumeral arthrodesis
   Show answer and explanation

   Correct answer: A. Arthroscopic superior capsular reconstruction

   Superior capsular reconstruction restores the superior restraint and depresses the humeral head in a young, active patient with an irreparable posterosuperior tear but preserved cartilage and an intact subscapularis, which is the key prerequisite. Reverse arthroplasty is generally reserved for older patients or those with cuff tear arthropathy and pseudoparalysis. Isolated acromioplasty risks anterosuperior escape by violating the coracoacromial arch, and arthrodesis is a salvage procedure for brachial plexus or failed reconstruction cases.

   Reference: Mihata T et al., Arthroscopy 2013 and subsequent outcome series; Rockwood and Matsen's The Shoulder, 6th ed. (2022)

10. Question 10 · Foot & Ankle

    A 20-year-old sprinter has 6 weeks of vague dorsal midfoot pain, with tenderness localised to the proximal dorsal navicular. Radiographs are normal but CT shows a non-displaced dorsal cortical stress fracture of the tarsal navicular. What is the most appropriate initial management?

    1. AWeight-bearing walking boot with return to running at 3 weeks
    2. BSix weeks of non-weight-bearing cast immobilisation
    3. CContinue training with a custom orthotic and analgesia
    4. DImmediate open reduction and internal fixation
    Show answer and explanation

    Correct answer: B. Six weeks of non-weight-bearing cast immobilisation

    The tarsal navicular is a high-risk (tension-side, relatively avascular central third) stress fracture site, and approximately 6 weeks of strict non-weight-bearing cast immobilisation followed by graded rehabilitation gives the best union rates for non-displaced fractures. Weight-bearing treatment and continued training are associated with delayed union, nonunion and displacement. Internal fixation is reserved for displaced fractures, complete fractures with a cystic or sclerotic nonunion, failure of non-operative treatment, or selected elite athletes after informed discussion.

    Reference: Mann's Surgery of the Foot and Ankle, 10th ed. (2023), stress fractures of the foot; AAOS Orthopaedic Knowledge Update: Foot and Ankle 6 (2020)