1. Mark Clatworthy Orthopaedic Surgeon Knee Specialist Middlemore Hospital

2.  Anatomy Refresher  How to diagnose and treat a meniscal tear, a ligament rupture and a patella dislocation  When should I take x rays of the knee and what should I take?  Practical on examination of the knee

4.  Mechanism of Injury  Typically a twisting injury on a loaded knee  Often sudden pain  Knee swells – variable time frame  Mechanical symptoms – catching, locking, clunking  Can give a feeling of instability

5.  Effusion  Springy block to extension if bucket handle  Focal joint line tenderness  Pain on meniscal grinding  Pain on loading and twisting the knee

6. Tense effusion is easily seen, Moderate effusion – patella tap Mild effusion - patella sweep

8.  Physical block  In young patient needs urgent meniscal repair  Don’t send to physiotherapist Urgent referral to orthopaedic surgeon We will see the patient that week

9.  Articular cartilage injury – unstable flap  Loose body  Stir up Osteoarthritis  Collateral Ligament Injury

10.  Locked knee refer  RICE  Symptoms will typically improve over a 6 week period then plateau  Refer if persistent pain or mechanical symptoms

11.  History taking key to diagnosis  Acutely injured knees are painful and swollen making the examination difficult  The diagnosis normally lies in the history

12.  Mechanism of injury Normally a side stepping or pivoting manoeuver or an awkward landing Often a non contact injury The posterolateral knee subluxes  Patient will feel a pop and the knee gave way

13.  Patient usually presents with a haemarthrosis  Knee may fell unstable with any twisting activity  Difficulty weightbearing due to bone bruising  The knee subluxes posterolaterally thus this area is usually tender

14.  Patients often present with a fixed flexion deformity. Initially this is due to bone bruising.  A bucket handle tear typically occurs only with multiple giving way episodes

15.  Must examine both knees. Large variation laxity  Fixed flexion deformity, reduced flexion

16. Occurs very early. Up to 5% loss of muscle bulk a day Very sensitive for a knee injury but not specific for a diagnosis

17.  The grading is determined by the increase in laxity compared to the normal contralateral knee  AOSSM Classification Grade 1 - 0 – 5 mm increase in laxity Grade 2 - 5 – 10 mm increase in laxity Grade 3 - >10mm

18.  Lachmann - anterior translation tibia

19.  Lachmann – Big leg, small hands

20. Anterior drawer decreased by posterior horn of the menisci – less positive than Lachmann

21.  Pivot shift test- reproduces the sensation of giving way. Lateral compartment subluxes

22.  Drop back seen with knee at 90°  Compare with other side

23.  Posterior drawer

24.  RICE  Do not immobilize. No knee brace required if no collateral ligament injury.  Need to start on quads and knee extension exercises immediately  Can weightbear as tolerated  Refer orthopaedic surgeon and physio

25.  Mechanism of injury Valgus force – rupture MCL Varus force – rupture LCL  Patient presents with pain and instability with coronal movement

26.  Palpate the ligament first.  MCL – Arises - medial femoral epicondyle Inserts – 6 - 8cm distally on the tibia  LCL - Arises from the lateral epicondyle Inserts into the fibula The LCL thus has more laxity than the MCL Can palpated as a cord like structure when the knee is placed in a figure 4 position

28.  RICE  Do not immobilize. Short ROM brace if Grade II or III  Need to start on quads and ROM exercises immediately  Can weightbear as tolerated if knee feels stable  Refer orthopaedic surgeon and physio

29.  Mechanism of Injury Typically twisting injury on a flexed knee or a direct blow  Patella may dislocate and stay there or self reduce

30.  Haemarthrosis  Medial retinacular tenderness  Patella apprehension sign

32.  Reduce dislocation  RICE  Aspirate if tense effusion  Ensure there is no osteochondral fragment  Immobilise in Zimmer splint – NO CASTS  Refer to orthopaedic surgeon  Refer to physio for static quads and straight leg raising exercises  Can weightbear as tolerated

33.  Patients with a knee effusion  Unable to weight bear  Ligamentous injury  Patella dislocation

34.  Weight bearing AP  45º weight bearing PA  Lateral  Skyline  AP Pelvis if unsure about hip

35.  Weight bearing X rays are critical

38.  Mandatory for ACC knee injuries  Orthopaedic surgeon can not get an ACC funded MRI scan without them  So if patient able to weightbear always order weightbearing knee X rays

39.  Multi ligament knees  ACL & PCL avulsions  Locked knees  Patella dislocations with osteochondral fragments

40.  All patients with suspicion of a - ligament tear - meniscal injury - patella dislocation

41.  Patella dislocations  Cruciate ligament injuries  Collateral ligament injuries  No meniscal tears

42.  Only those with painful tense haemarthrosis.  I aspirate very few  Aspirate superio-lateral with a large >= 16 gauge angiocath. Inject Xylocaine with adrenaline Examine the knee after 5 minutes  If unsure refer

43. http://www.acc.co.nz/for-providers/clinical-best- practice/practical-workshops/WPC090892