Review of Critical Care Medicine

PATELLA:-

1. In transverse fracture of the patella the treatment is

a)Excision of a small fragment
b)Wire fixation
c)Plaster cylinder
d)Patellectomy

Transverse Patellar Fracture

Introduction

Transverse fractures of the patella  are the result of an indirect force, usually with the knee in flexion. Fracture may be caused by sudden voluntary contraction of the quadriceps muscle or sudden forced flexion of the leg with the quadriceps contracted. The level of fracture is commonly in the middle. Associated tearing of the patellar retinacula depends upon the force of the initiating injury. The activity of the quadriceps muscle causes upward displacement of the proximal fragment, the magnitude of which depends on the extent of the retinacular tear.

Clinical Findings 

Swelling of the anterior knee region is caused by hemarthrosis and hemorrhage into the soft tissues overlying the joint. If displacement is present, the defect in the patella can be palpated, and active extension of the knee is lost. A straight leg raise may be preserved if the retinacula is intact.

Treatment

Nondisplaced fractures can be treated with a walking cylinder cast or brace for 6-8 weeks followed by knee rehabilitation. Open reduction is indicated if the fragments are displaced > 3 mm or if articular step-off is > 2 mm. The fragments must be accurately repositioned to prevent early posttraumatic arthritis of the patellofemoral joint. If the minor fragment is small (no more than 1 cm in length) or severely comminuted, it may be excised and the quadriceps or patellar tendon (depending upon which pole of the patella is involved) sutured directly to the major fragment. Whenever possible, internal fixation of anatomically reduced fragments should be done, allowing early motion of the knee joint. This is best achieved by figure-of-eight tension banding over two longitudinal parallel K-wires.

Accurate reduction of the articular surface must be confirmed by lateral radiographs taken intraoperatively.

2. Comminuted Patellar Fracture

Comminuted fractures of the patella are usually caused by a direct force. Most often, little or no separation of the fragments occurs because the quadriceps retinaculum is not extensively torn. Severe injury may cause extensive destruction of the articular surface of both the patella and the opposing femur.

If comminution is not severe and displacement is insignificant, immobilization for 8 weeks in a cylinder extending from the groin to the supramalleolar region is sufficient.

Severe comminution can often be treated with ORIF with addition of a cerclage wire, but on rare occasions excision of the patella and repair of the defect by imbrication of the quadriceps expansion is the only viable alternative. Excision of the patella can result in decreased strength, pain in the knee, and general restriction of activity. No matter what the treatment, high-energy injuries are frequently complicated by chondromalacia patella and patellofemoral arthritis. Note:-Satisfactory results have been reported with use of the tension band wire and its modification in treating comminuted and displaced patellar fractures although most authors recommend patellectomy when less than half of the articular surface of the patella remains intact

2. Communited fracture of patella is treated by-

A)Tension wire bandage
b)Surgery and immobilisation
c)Conservative
d)Patellectomy

3. Recurrent dislocation of patella is most often associated with-
a)Abnormally high patella
b)Abnormally low patella
c)Bow leg
d)Quadriceps contracture

The majority of patients with complaints of patellar pain and instability will have objective abnormalities of the extensor mechanism and patellofemoral joint. These abnormalities are preexisting and developmental. Major examples include a shallow trochlea, an increased quadriceps angle (Q-angle), a vastus medialis obliquus (VMO) deficiency, and a patella alta(high)

PATELLA ALTA:- The Patella is high-lying in the shallower part of intercondylar groove.

ARTHROSCOPIC LATERAL RELEASE
The indication for arthroscopic lateral release (Fig. 87.10) is a tight lateral retinaculum that is producing the patient’s symptoms, which have not responded to appropriate nonoperative treatment. If it is not tight, don’t release it. If the patient has a large Q angle as well, an isolated lateral release will not be sufficient; the tibial tubercle will usually have to be moved also.

4.Clergymen’s knee is due to involvement of-

a)Prepatellar Bursa c)Suprapatellar
b) Intrapatellar bursa d) Infrapatellar bursa

5.Treatment of displaced transverse fracture of patella –
a) POP b) Tension band wiring
c) Screw d) Patellectomy

Ans given in guides is a b and d but its wrong as  # is displaced

Nondisplaced fractures can be treated with a walking cylinder cast or brace for 6-8 weeks followed by knee rehabilitation. Open reduction is indicated if the fragments are displaced > 3 mm or if articular step-off is > 2 mm. The fragments must be accurately repositioned to prevent early posttraumatic arthritis of the patellofemoral joint. If the minor fragment is small (no more than 1 cm in length) or severely comminuted, it may be excised and the quadriceps or patellar tendon (depending upon which pole of the patella is involved) sutured directly to the major fragment. Whenever possible, internal fixation of anatomically reduced fragments should be done, allowing early motion of the knee joint. This is best achieved by figure-of-eight tension banding over two longitudinal parallel K-wires

6 Which one of the following structures is at least risk of damage in knee dislocation? (UPSC 02)
a)Cruciate ligaments
b)Common peroneal nerve
c)Patella
d)Popliteal artery

Ans. is ‘c’ i.e., Patella [Ref : Apley’s 8e p. 713, Adam’s outline of fracture p. 237]

Normally the knee is held stable by –
I) Its strong ligaments (the two cruciate ligaments, the medial and lateral ligaments and the joint capsule) and
ii) Protective control of powerful Quadriceps muscle.
Dislocation is possible only if some or all of the ligaments are ruptured.
Dislocation usually occurs in the posterolateral or anteromedical direction
Complications of knee dislocation
Most feared complication of knee dislocation are – .
.Injury to the popliteal artery
.Injury to the major nerve trunks behind the knee (all of these are especially vulnerable when the tibia is displaced backwards)
Also know
Nerve trunks in posterior relation to the knee joint
.Tibial nerve (at the middle)
.Common peroneal nerve (posterolaterally)

The anatomic system takes into account the soft tissue and is seen in Table . Type III injuries are most common, with type IIIL having a poor outcome when compared to type IIIM. There is a high incidence of arterial injury (on average, 33%) including intimal tears rather than complete disruptions.

Neurologic Examination. Neurologic examination includes a thorough evaluation of the peroneal nerve, including EHL and tibial anterior strength and sensation to the EHL and tibialis anterior strength. There is a 14% to 35% incidence of injury; the most common occurrence is type III L (varus) as a result of traction. The tibial nerve may be involved and can be assessed with FHL and gastrocnemius/soleus strength along with sensation over the lateral border and planter surface of the foot.

7.Transverse fracture of patella in a young adult. What is the treatment of choice?
a) Tension band wiring b) Cylinder cast
c) Patellectomy d) Conservative

8.Treatment of fracture patella in.24 year old young male is –

a)Patellectomy if undisplaced
b)No treatment required
c)Internal fixation if communited fracture
d)POP in full extension

9.In a young patient, transverse fracture of patella is best treated by –
a)Patellectomy
b)Application of cylindrical POP cast
c)Strict bed rest with quandriceps exercises
d)Tension band wiring following by POP cast

ans given is C in guides but i think its wrong.

Whenever possible, internal fixation of anatomically reduced fragments should be done, allowing early motion of the knee joint.

10.The most common cause for anterior knee pain is –
a)Prepatellar bursitis
b)Congenital discoid meniscus
c)Plica syndrome
d)Chondromalacia patellae

Ref Apley p. 469-470]

The plica syndrome
.The plica is remnant of an embryonis synovial partition which persists into adult life.
.During development of embryos the knee is divided into three cavities
.a large Suprapatellar pouch and beneath this
.Medial and lateral comparments.
.These three cavities are separated from each other by membranous septa. Later these partitions disappear leaving a single cavity. But sometimes part of septum may persist as a synovial pleat or plica.
.This is seen in over 20% people.The plica in itself is not pathological. But if acute trauma, repetitive strain or some underlying disorder causes inflammation the plica may become oedematous, thickened and eventually fibrosed. It then acts as a light bowstring impinging on other structures in the joint and causing further synovial irritation.
Clinical feature
.An adolescent or young adult complains of an ache in the front of the knee with intermittent episodes of clicking or `giving way’ there may be history of trauma or markedly increased activity
.Symptoms are aggravated on exercise or climbing stairs
.The most characteristic feature is tenderness near upper pole of the patella.

11.Usual site of Tubercular bursitis –
a) Prepatelar b) Subdeltoid
c) Subpatellar d) Trochanteric
e) None

12.Usual site of TB bursitis –
a) Prepatellar b) Subacromial
c) Subdeltoid d) Subpatellar
e) Trochanteric

13.Housemaids knee is inflammation of bursa –
a) Subpatellar b) Suprapatellar
c) Infrapatellar d) Pre patellar

14.Patella is at a higher level in –
a)Recurrent dislocation
b)Nail-patella syndrome
c)Rheumatoid arthritis
d)Plica syndrome

15.Nail patella syndrome is characterised by –
a) Iliac horn b) Sacral horn
c) Absent patella d) Knee deformity
e) Dislocation of patella

The hallmark features of this syndrome are poorly developed fingernails, toenails, and patellae (kneecaps).

Bones and joints
Patellar involvement is present in approximately 90% of patients; however, patellar aplasia occurs in only 20%.
In instances in which the patellae are smaller or luxated, the knees may be unstable.
The elbows may have limited motion (eg, limited pronation, supination, extension).
Subluxation of the radial head may occur.
Arthrodysplasia of the elbows is reported in approximately 90% of patients.
General hyperextension of the joints can be present.
Exostoses arising from the posterior aspect of the iliac bones are present in as many as 80% of patients; this finding is considered pathognomonic for the syndrome.

16. Patellar tendon bearing P.O.P. cast is indicated in the following fracture :
A.Patella
B.Tibia
C.Medial malleolus
D.Femur

Ans is B

17.