Pelvis and lower limb

Question 1

AVN of the femoral head

-what can cause this?

Answer 1

may be primary / idiopathic or secondary to alcohol abuse, steroids, hyperlipidaemia or thrombophilia.

Question 2

What is seen on imaging of AVN of femoral head?

Answer 2

Early cases may only show changes on MRI (pre‐radiographic AVN) whilst later cases show patchy sclerosis of the weight bearing area of the femoral head with a lytic zone underneath formed by granulation tissue from attempted repair. The lytic zone gives rise to the classic “hanging rope sign” on Xray. The femoral head may then collapse with irregularity of the articular surface and subsequent secondary OA.

Question 3

What can be done early for AVN femoral head?

Answer 3

If the condition is detected early enough (pre‐collapse), drill holes can be made up the femoral neck and into the abnormal area in the head in an attempt to relieve pressure (decompression), promote healing and prevent collapse. Once collapse has occurred, the only surgical option is THR.

Question 4

What is gluteal bursitis/gluteal cuff syndrome?

Answer 4

The broad tendinous insertion of the abductor muscles (predominantly the gluteus medius) is under considerable strain and is subject to tendonitis and degeneration leading to tendon tears. The trochanteric bursa can also become inflamed. The condition is similar to rotator cuff problems of the shoulder.

Question 5

What is seen clinically in trochanteric bursitis?

Answer 5

Patients have pain and tenderness in the region of the greater trochanter with pain on resisted abduction.

Question 6

What is the treatment for trochanteric bursitis?

Answer 6

Treatment is with analgesic, anti‐inflammatories, physiotherapy (to strengthen other muscles and avoid abductor weakness) and steroid injection. No surgical treatment has a proven benefit.

Question 7

Describe the classical history for a meniscal injury

Answer 7

Meniscal injuries classically occur with a twisting force on a loaded knee (eg turning at football, squatting). The patient localizes pain to the medial (majority) or lateral joint line and an effusion develops by the following day. The patient then complains of pain and usually has mechanical symptoms – either a catching sensation or “locking” where they have difficulty straightening the knee with a 15° or so block to full extension. Patients knees may feel about to give way if a loose meniscal fragment is caught in the knee when walking.

Question 8

Describe the classical history for an ACL rupture

Answer 8

ACL ruptures usually occur with a higher rotational force, turning the upper body laterally on a planted foot (leading to internal rotation force on the tibia), often at football, rugby, skiing or another high impact sport. A “pop” is usually felt or heard and the patient usually develops a haemarthrosis (an effusion due to bleeding in the joint, in this case from the vascular supply within the ACL) within an hour of the injury and deep pain in the knee. Chronically, the patient may then complain of rotatory instability with their knee giving way when turning on a planted foot (due to excessive internal rotation of the tibia).

Question 9

Describe what can happen in valgus stress injuries?

Answer 9

Valgus stress injuries (eg rugby tackle from the side) will usually tear the medial collateral ligament (MCL) with higher forces also potentially damaging the ACL and risking lateral tibial plateau fracture.

Question 10

What can happen in a direct blow to the anterior tibia?

Answer 10

A direct blow to the anterior tibia with the knee flexed (eg motorcycle crash) or hyperextension may rupture the PCL

Question 11

What can happen in a varus stress injury?

Answer 11

A varus stress injury may rupture the lateral collateral ligament (LCL) with or without damage to the PCL.

Question 12

Why can it be difficult to examine the knee after injury? what is done to overcome this difficulty?

Answer 12

The knee can be difficult to examine in the aftermath of an injury as pain and apprehension may limit examination findings and it is often helpful to see these patients again in 2-7 days to re-examine. If the injury is thought to be significant, with a suspicious history and possible multiple ligament injuries, an early MRI will help delineate the extent of injury.

Question 13

How can a locked knee be confirmed?

Answer 13

MRI scan

Question 14

What do 25% of ACL ruptures also have?

Answer 14

Note also that around 25% of acute ACL ruptures also have a meniscal tear.

Question 15

Which meniscal tear is more common?

Answer 15

Medial meniscal tears are approximately 10 times more common than lateral meniscal tears due to the fact that the medial meniscus is more fixed and less mobile than the lateral meniscus and the force from pivoting movements is centred on the medial compartment.

Question 16

Describe the different patterns of meniscal tears?

Answer 16

Meniscal tears can have various patterns including longitudinal tears, radial tears, oblique tears and horizontal tears. Large longitudinal tears may result in a “bucket handle tear” where a large meniscal fragment is able to flip out of its normal position and displace anteriorly or into the intercondylar notch where the knee locks and is unable to fully extend due to mechanical obstruction from the trapped meniscal fragment.

Degenerate meniscal tears can occur as the meniscus weakens with age. The meniscus can tear spontaneously or with a seemingly innocuous injury. Degenerate tears tend to have complex patterns with horizontal, longitudinal and radial components. Degenerate tears are probably the first stage in many cases of knee osteoarthritis.

Question 17

What is the treatment for meniscal tear?

Answer 17

• meniscal repair in a tear of outer 1/3 meniscus in a young patient (90% are not suitable)
• pain and inflammation is self limiting (although they do not heal)
• steroid injection for degenerate tears
• In acute tears, if the pain or mechanical symptoms do not settle within around 3 months then arthroscopic partial menisectomy can be performed with around 70‐80% improvement in symptoms. Knees with degenerate changes on xray (loss of joint space, sclerosis, osteophytes) or MRI (hyaline cartilage loss, bone marrow oedema) are unlikely to benefit from arthroscopic menisectomy as removal of meniscal tissue may increase the stress on already worn / damaged surfaces.

Question 18

Who are good candidates for ACL repair?

Answer 18

Professional sportsmen or women who need to get back to their profession as quick as possible usually proceed straight to ACL reconstruction and those whose knees give way on sedentary activity or those who have a strong desire to get back to high impact sport but cannot do so despite physiotherapy are good candidates for ACL reconstruction.

• repair using a tendon graft
• may take up to a year to get back to high impact sport

Question 19

How are MCL tears treated?

Answer 19

MCL injuries are fairly common however the MCL is a fairly forgiving knee ligament with healing expected in the majority of partial and complete tears and little or no instability. Patients may have laxity and pain on valgus stress with tenderness over the origin or insertion of the MCL. Acute tears are usually treated in a hinged knee brace. Chronic MCL instability can be treated with MCL tightening (advancement) or reconstruction with tendon graft

Question 20

What is the concern with complete knee dislocations?

Answer 20

Complete knee dislocations result in rupture of all four of the knee ligaments and have a high incidence of neurovascular injury.

They should be reduced as an emergency and may require external fixation for temporary stabilization. Intimal tears can occur which later thrombose and therefore regular checks on the circulation of the foot are mandatory.

Any concern with the distal circulation mandates a vascular surgery assessment and vascular stenting or by‐pass may be required.

Reperfusion may result in compartment syndrome especially after prolonged ischaemia and fasciotomies may be necessary. Patients usually require multiple ligament reconstruction.

Question 21

Extensor mechanism rupture - how can this occur?

-how does this affect?

Answer 21

The patellar tendon or quadriceps tendon can rupture with rapid contractile force which can occur after lifting a heavy weight, after a fall or spontaneously in a severely degenerate tendon.

Patellar tendon ruptures tend to occur in a younger age group (<40) with quadriceps tendon rupture in older patients (over 40).

Question 22

What are predisposing factors to extensor mechanism ruptures?

Answer 22

Predisposing factors include history of tendonitis, chronic steroid use or abuse (body builders), diabetes, rheumatoid arthritis and chronic renal failure. Quinolone antibiotics (eg ciprofloxacin) can cause tendonitis and can risk tendon ruptures. Steroid injections for tendonitis of the extensor mechanism of the knee should be avoided due to high risk of tendon rupture.

Question 23

What is seen clinically with a extensor mechanism rupture and what is treatment?

Answer 23

Patients will also usually have an obvious palpable gap in the extensor mechanism and Xrays may reveal a high (PT rupture) or low lying (quads rupture) patella. Partial tears can also occur which may have some extensor mechanism function but reduced power. In obese patients the gap may not be obvious and ultrasound may determine the extent of the injury.

In clinically obvious cases or with ultrasound confirmation, the treatment of complete and substantial partial tears is surgical with tendon to tendon repair or reattachment of the tendon to the patella.

Question 24

what is patellofemoral dysfunction?

Answer 24

Patellofemoral dysfunction describes disorders of the patellofemoral articulation resulting in anterior knee pain. It encompasses and in many cases is synonymous with various diagnoses including chondromalacia patellae (softening of the hyaline cartilage), adolescent anterior knee pain and lateral patellar compression syndrome.

Patients tend to complain of anterior knee pain, worse going downhill, a griniding or clicking sensation at the front of the knee and stiffness after prolonged sitting causing “pseudolocking” where the knee acutely stiffens in a flexed position (in contrast to true locking from a bucket handle meniscal tear).

The vast majority (at least 90%) of sufferers improve with physiotherapy aimed at rebalancing the quadriceps muscles (specifically strengthening vastus medialis obliquus, VMO). Taping may alleviate symptoms

Question 25

How can patellar dislocation happen? what occurs? what is seen on xray?

Answer 25

Patellar dislocation can occur with a direct blow or sudden twist of the knee. The patella virtually always dislocates laterally and may spontaneously reduce wen the knee is straightened or rarely may require to be manually manipulated back into position.

When the patella dislocates, the medial patellofemoral ligament tears and osteochondral fracture may occur as the medial facet of the patella strikes the lateral femoral condyle which may be suggested by a small opacification on Xray. A lipo‐haemarthrosis occurs with characteristic Xray appearance.

Question 26

What are the predisposing factors of patellar dislocation and what is the management?

Answer 26

Predisposing factors include ligamentous laxity, female gender, shallow trochlear groove, genu valgum, femoral neck anteversion and a high riding patella (patella alta).

The risk of recurrent instability decreases with age and physiotherapy to strengthen the quadriceps may help. The risk of recurrent dislocation after first time dislocation is around 10%

Question 27

what is hallux rigidus?

• what is the conservative treatment?
• what is the gold standard treatment?

Answer 27

Hallux rigidus is OA of the first MTPJ. It can be primary (degenerative) or secondary to osteochondral injury.

Conservative treatment may involve the wearing of stiff soled shoe to limit motion at the MTPJ. A metal bar can be inserted into the sole of a shoe. In early cases where dorsal osteophytes impinge during dorsiflexion, removal of osteophytes (cheilectomy) may help.

The “gold standard” surgical treatment is arthrodesis. Successful fusion should alleviate pain with the small sacrifice of no motion (the toe is usually pretty stiff anyway). Arthrodesis prevents women wearing high heels. 1st MTP joint replacements including ceramic total joint replacements and metal hemi‐arthroplasties are in use but the failure rates are quite high and once failure occurs, salvage surgery is difficult and results are usually disappointing.

Question 28

What is a mortons neuroma?

Answer 28

Plantar interdigital nerves (from the medial and lateral plantar nerves) overlying the intermetatarsal ligaments can be subjected to repeated trauma. Irritated nerves can become inflamed and swollen (forming a neuroma). Patients complain of a burning pain and tingling radiating into the affected toes. Women are four times more commonly affected and the wearing of high heels has been implicated as a cause. The third interspace nerve is most commonly involved followed by the second.

Question 29

What is seen on clinical examination of a mortons neuroma?

Answer 29

Clinical examination may reveal loss of sensation in the affected web space. Medio‐lateral compression of the metatarsal heads (exerted by squeezing the forefoot with your hand) may reproduce symptoms or produce a characteristic “click”; this is Mulder’s click test.

Question 30

What is the investigation and management of a mortons neuroma?

Answer 30

Ultrasound may be used for diagnosis by demonstrating a swollen nerve.

Conservative management involves the use of a metatarsal pad or offloading insole. Steroid and local anaesthetic injections may relieve symptoms and aid diagnosis.

A neuroma can be excised. However, some patients continue to experience pain and there is a small risk of recurrence.

Question 31

Where do metatarsal stress fractures usually occur?

Answer 31

Metatarsal stress fractures most commonly occur in the 2nd metatarsal followed by the 3rd.

Question 32

Who is affected by metatarsal stress fractures?

Answer 32

They may occur in runners, in soldiers on prolonged marches, in dancers or during distance walking in people not conditioned or used to prolonged walks.

Question 33

What is the investigation and management of metatarsal stress fractures?

Answer 33

Xrays may not demonstrate a fracture for around 3 weeks until resorption at the fracture ends occurs or callus begins to appear. Bone scan may be useful to confirm the diagnosis. Prolonged rest for 6‐12 weeks in a rigid soled boot is required to allow healing and resolution of symptoms.

Question 34

Tendonitis of the achilles tendon:

• what causes this
• where is pain felt

Answer 34

Repetitive strain (from sports) which leads to a peritendonitis or due to degenerative process with intrasubstance microtears.

Quinolone antibiotics (ciprofloxacin etc), rheumatoid arthritis, other inflammatory arthropaties and gout may also predispose to tendonitis.

Pain can be in the main substance of the Achilles tendo or at its insertion in the calcaneus.

Question 35

What is the treatment of achilles tendonitis?

Answer 35

Treatment is rest, physiotherapy conditioning, use of a heel raise to offload the tendon and use of a splint or boot. Resistant cases may benefit from tendon decompression and resection of paratenon however scars in this area can be problematic and the condition is usually self‐ limiting.

NOT steroid injection because of risk of rupture

Question 36

What causes achilles tendon rupture? what is seen clinically?

Answer 36

Tendon rupture usually occurs in middle aged or older groups and is usually due to degenerative changes within the tendon or recent tendonitis. Sudden deceleration with resisted calf muscle contraction (eg lunging at squash) leads to sudden pain (like being kicked in the back of the leg) and difficulty weight bearing.

Weakness of plantar flexion and a palpable gap in the tendon are usually apparent. No plantarflexion of the foot is seen when squeezing the calf (Simmonds test).

Question 37

what are the treatment options for achilles tendon rupture?

Answer 37

• suture repair of damaged tendon

- casting in the equinous position (avoids wound problems)

Question 38

What is plantar fasciitis?

Answer 38

This is another self‐limiting repetitive stress / overload or degenerative condition of the foot. Pain with walking is felt on the instep of the foot (at the origin of the plantar aponeurosis on the distal plantar aspect of the calcaneal tuberosity) with localized tenderness on palpation of this site.

Diabetes, obesity and frequent walking on hard floors with poor cushioning in shoes may be causative factors. The cushioning heel fat pad atrophies with age.

Question 39

what is the treatment for plantar fasciitis?

Answer 39

Rest, Achilles and plantar fascia stretching exercises and a gel filled heel pad may help. Corticosteroid injection may also alleviate symptoms. Symptoms can take up to two years to resolve. Surgical release of the plantar fascia is of dubious value and risks injury to the plantar nerves

Question 40

what is tibialis posterior tendon disfunction?

Answer 40

The tibialis posterior tendon inserts predominantly onto the medial navicular and serves to support the medial arch of the foot (as well as being a plantarflexor and invertor of the foot). The tendon is under repeated stress and particularly with degeneration can develop tendonitis, elongation and eventually rupture. Synovitis form RA can also result in tendon rupture.

Question 41

How should tibialis posterior tendon rupture be managed?

Answer 41

Tendonitis should be treated with a splint with a medial arch support to avoid rupture. If this fails to settle symptoms, surgical decompression and tenosynovectomy may prevent rupture. Elongation or rupture leads to loss of the medial arch with resulting valgus of the heel and flattening of the medial arch of the foot. Subsequent degenerative OA of the hindfoot and midfoot may occur. If the foot remains supple with no OA present, a tendon transfer may be performed to try to prevent secondary OA with a calcaneal osteotomy to reduce stress often performed. Once OA ensues, the most appropriate surgical treatment if symptoms are severe is arthrodesis.

Question 42

What is pes cavus?

Answer 42

Pes cavus is an abnormally high arch of the foot. It can be idiopathic but is often related to neuromuscular conditions including Hereditary Senory and Motor Neuropathy, cerebral palsy, polio(unilateral) and spinal cord tethering from spina bifida occulta. Claw toes often accompany pes cavus. Its development is poorly understood.

Pain from pes cavus may be treated with soft tissue releases and tendon transfer (lateral transfer of tibialis anterior) if supple, or calcaneal osteotomy if more rigid. Severe cases may require arthrodesis.

Question 43

Why do claw and hammer toes occur?

Answer 43

Claw toes and hammer toes occur due to acquired imbalance between the flexor and extensor tendons. Claw toes have hyperextension at the MTPJ with hyperflexion at the PIPJ and DIP. Hammer toes are similar but have hyperextension at the DIPJ.

Question 44

What is the management of claw and hammer toes?

Answer 44

Claw and hammer toes can be painful and can rub on footwear causing corns and skin breakdown. Toe “sleeves” and corn plasters can prevent skin problems. Surgical solutions include tenotomy (division of an overactive tendon), tendon transfer, arthrodesis (PIPJ) or toe amputation.