INJURIES AROUND KNEE JOINT MBBS CLASS.pptx

INJURIES AROUND KNEE JOINT

1. INJURIES AROUND KNEE JOINT BY DR. BHRAMPREET

2. ANATOMY Largest and most superficial joint. Hinge joint Flexionn and extension Tibia and femur ( tibio femoral joint) Patella and femoral condyles ( patello femoral joint) Fibula is not a part of the joint Stability ligaments Collateral ligaments: medial and lateral ligaments Cruciate ligaments: anterior and posterior

3. Menisci Fibrocartilage Act as shock absorbers Medial meniscus- c shaped, broader posteriorly than anteriorly Lateral meniscus: almost circular, freely movable, smaller

4. MECHANISM OF KNEE INJURIES The knee joint is subjected to a variety of forces during day-to-day activities and sports. . The nature of the forces may be direct or indirect. An indirect force on the knee may be: ( i ) valgus (ii) varus (iii) Hyperextension or (iv) twisting

5. CONDYLAR FRACTURES OF FEMUR Condylar fractures of the femur are of three types: supracondylar fractures (ii)  intercondylar fractures – T or Y types and (iii)  unicondylar fractures – medial or lateral. These fractures commonly result from a direct trauma to the lower end of the femur.

6. Diagnosis of these fractures is suggested by pain, swelling and bruising around the knee. Diagnosis is made on X-rays. A careful assessment of the intra-articular extension of the fracture and joint incongruity must be made.

7. TREATMENT Unicondylar fractures: If undisplaced , a long leg cast is given for 3-6 weeks, followed by protected weight bearing. If displaced, open reduction and internal fixation with multiple cancellous screws is performed. A buttress plate may be required in some cases

8. Intercondylar fractures: The aim of treatment is to restore congruity of the articular surface as far as possible. In displaced T or Y fracture with minimal comminution , the joint is reconstructed by open reduction and internal fixation with Condylar blade-plate, DCS and LCP are popular implants. Comminuted fractures are difficult to accurately reconstruct, but well done open reduction and internal fixation permits early knee mobilisation and thus better functions.

9. In selected comminuted fractures, conservative treatment in skeletal traction may be the best option, and give acceptable results.

10. Supracondylar fractures : It is best to treat displaced supracondylar fractures with internal fixation. This could be done by closed or open techniques. Nail or plate may be used.

11. COMPLICATIONS Knee stiffness : Residual knee stiffness sometimes remains because of dense intraand peri -articular adhesions. A long course of physiotherapy is usually rewarding. Arthrolysis may be required in resistant cases. Osteoarthritis : Fractures with intra-articular extension give rise to osteoarthritis a few years later.

12. Malunion : A malunion may result in varus or valgus deformities, sometimes requiring a corrective osteotomy .

13. FRACTURES OF PATELLA This is a common fracture. It may result from a direct or an indirect force. In a direct injury, as may occur by a blow on the anterior aspect of the flexed knee, usually a comminuted fracture results. Sometimes, a sudden violent contraction of the quadriceps, gives rise to a fracture.

14. CLINICAL FEATURES The patient complains of pain and swelling over the knee. In an undisplaced fracture the swelling and tenderness may be localised over the patella. A crepitus is felt in a comminuted fracture. In displaced fractures, one may feel a gap between the fracture fragments. The patient will not be able to lift his leg with the knee in full extension (extensor lag)

15. Radiological examination: Antero-posterior and lateral X-rays of the knee are sufficient in most cases. In some undisplaced fractures, a ‘skyline view’ of the patella may be required.

16. TREATMENT It depends upon the type of fracture, and in some cases on the age of the patient. a) Undisplaced fracture : A plaster cast extending from the groin to just above the malleoli , with the knee in full extension (cylinder cast) should be given for 3 weeks, followed by physiotherapy.

17. b) Clean break with separation of fragments (two-part fracture): The pull of the quadriceps muscle on the proximal fragment keeps the fragments apart, hence an operation is always necessary. The operation consists of reduction of the fragments, fixing them with tension-band wiring (TBW) and repair of extensor retinaculae .

18. c) Comminuted fracture : In comminuted fractures with displacement, it is difficult to restore a perfectly smooth articular surface, so excision of the patella ( patellectomy ) is the preferred option.

19. COMPLICATIONS Knee stiffness Extensor weakness Osteoarthritis

20. TIBIAL PLATEAU FRACTURES These are common fractures sustained in two wheeler accidents when one lands on the knee. Either or both condyles of tibia are fractured. The mechanism of injury is: (a) an indirect force causing varus or valgus force on the knee or (b) a direct hit on the knee.

21. Types of fracture: These fractures commonly occur in six patterns ( Schatzker types). Type I-IV involve only one condyle , lateral or medial. Type V and VI are more complex inter condylar fractures.

22. Symptoms and signs : The patient complains of pain and swelling, and inability to bear weight. Often crepitus is heard or felt. Diagnosis can be made on X-rays. CT scan may be required for accurate evaluation.

23. Treatment : Both conservative and operative methods can be used. Conservative methods are used for minimally displaced fractures, and those in elderly people. Surgical treatment with orif and plating.

24. MENISCAL INJURIES OF THE KNEE These constitute a common group of injuries peculiar to the knee, frequently being reported with increasing sporting activity. The injury is sustained when a person, standing on a semi-flexed knee, twists his body to one side. The twisting movement, an important component of the mechanism of injury, is possible only with a flexed knee.

25. The meniscus may be torn with a minor twisting, as may occur while walking on uneven surface. . The medial meniscus gets torn more often because it is less mobile (being fixed to the medial collateral ligament). A degenerated meniscus in the elderly may get torn by minimal or no injury.

26. Types of meniscal tear: The bucket-handle tears are the commonest type; others are radial, anterior horn, posterior horn and complex tears.

27. CLINICAL FEATURES The patient is generally a young male actively engaged in sports like football, volleyball etc. The presenting complaint is recurrent episodes of pain, and locking of the knee. At times, the patient complains of a ‘ jhatka ’, a sudden jerk while walking, or‘something flicking over’ inside the joint.

28. CLINICAL FEATURES This may be followed by a swelling, appearing after a few hours and lasting for a few days. After some time, the pain becomes persistent but with little or no swelling followed by a swelling appearing overnight as effusion collects. After the effusion subsides, the knee may remain in about 10 degrees of flexion, beyond which the patient is unable to extend his knee (locking).

29. . The displaced fragment sometimes returns to its original position spontaneously and thus the original episode of locking may never be noticed. The history of sudden locking and unlocking, with a click located in one or other joint compartment, is diagnostic of a meniscus tear.

30. ON EXAMINTAION In a typical episode presenting after injury, the knee may be swollen. There may be tenderness in the region of the joint line, either anteriorly or posteriorly . The knee may be locked. The manoeuvres carried out to detect a hidden meniscus tear are McMurray's and Apley's test

31. RADIOLOGICAL EXAMINATION With meniscal tears there are no abnormal X-ray findings. X-rays are taken to rule out any associated bony pathology. MRI is a non-invasive method of detecting meniscus tears. It is a very sensitive investigation, and sometimes picks up tears which are of no clinical significance.

32. ARTHROSCOPY : This is a technique where a thin endoscope, about 4-5 mm in diameter – the arthroscope , is introduced into the joint through a small stab wound, and inside of the joint examined

33. TREATMENT Treatment of acute meniscal tear: If the knee is locked, it is manipulated under general anaesthesia . No special manoeuvre is needed. Followed by immobalisation for 2-3 weeks. Treatment of a chronic meniscal tear: Once the diagnosis is established clinically, the treatment is to excise the displaced fragment of the meniscus. Now-a-days, it is possible to excise a torn meniscus arthroscopically .

34. RARE INJURIES AROUND KNEE Dislocation of the knee: This rare injury results from severe violence to the knee so that all of its supporting ligaments are torn. It is a major damage to the joint, and is often associated with injury to the popliteal artery. Treatment is by reduction followed by immobilisation in a cylinder cast.

35. Disruption of extensor apparatus : Injury from sudden quadriceps contraction most often results in fracture of the patella. Sometimes, it may result in tearing of the quadriceps tendon from its attachment on the patella, or tearing of the attachment of the patellar tendon from the tibial tubercle. In either case, operative repair of the tendon is required.

36. Dislocation of the patella: The patella usually dislocates laterally. It can be one of three types: acute dislocation; recurrent dislocation and habitual dislocation