Knee Injuries in the Skeletally Immature Adolescent Athlete: Current Questions and Challenges

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1 Knee Injuries in the Skeletally Immature Adolescent Athlete: Current Questions and Challenges Corey Dean MD Internal Medicine-Pediatrics, CAQ Sports Medicine

2 Mascots.

3 Mascots.

4 Objectives 1. Discuss the most common cause of adolescent knee pain, ways to treat this without referral and when to allow the athlete to return to play. 2. Discuss the various apophysitis/tendonitis injuries associated with the skeletally immature knee. 3. Discuss the anterior cruciate ligament (ACL) epidemic in young women, treatment controversies, and ways to prevent them. 4. Discuss the one knee injury you do not want to miss and why referral early is so crucial.

5 Anatomy of the knee-3 compartments The Knee is broken down into 3 compartments: 1. Patellofemoral (including bursa) 2. Ligamentous 3. Meniscal

6 Case 1 An 17-year-old cross country runner c/o anterior knee pain for 6 weeks. Provoked by walking up and down stairs and sitting in class. No history of locking, catching, swelling, or instability. On physical exam, Mild tenderness over the medial aspect of the patella. Quadriceps tone was poor over vastus medialis. + Patellar inhibition testing (subluxation tenderness).

7 Patellofemoral knee physical exam

8 Patellofemoral Knee Dysfunction(PFKD) Pathophysiology of PFKD-most common knee injury in adolescents Weakness of the quadiceps, specifically VMO dysplasia Tight iliotibial bands Tight hamstring muscles Weakness or tightness of the hip muscles (adductors, abductors, external rotators) Tight calf muscles

9 Q angle Woman more predisposed to PFKD secondary to widened Q angle Knock knees or genu valgum

10 PFKD Diagnostic Testing: 1. No testing is neededclinical diagnosis 2. X-rays-usually normal. Rare cases of severe PFKD leading to arthritic changes.

11 PFKD-Treatment - Running was reduced (preferably on grass or on a treadmill). - Keep the athlete in the game-swimming as cross training. - Ice massage was recommended three to four times daily over patellofemoral complex. - Open and closed-chain exercises with an emphasis on the vastus medialis obliques strengthening. - A lower-extremity flexibility program was also started, focusing on the hamstrings/quadriceps. - Use of NSAIDs as needed.

12 PFKD-Return to play -90/90 rule (90% range of motion and 90% strength in comparison to the unaffected side) -10% rule - Graded progression in return to athletic competition in using pain as your guide to increase mileage of running (by 10% per week). If pain recurs, then plateau running.

13 Foot Exam and Running shoes Importance of the feetproper running shoes were recommended and evaluation of foot alignment was assessed (+/-orthotics).

14 Orthotics

15 Case 2 14 year old basketball player has c/o anterior knee pain for 3 months. He has grown 4 inches in the past 5 months. No locking or giving way. -Provoked by jumping, kneeling and palliated by rest. -On examination, tenderness localized to the tibial tubercle. All other tests are normal.

16 Differential Diagnosis for Anterior Knee Pain (a)osgood-schlatter disease (b)inferior patellar pole traction apophysitis (Sinding-Larsen disease) (c)patellofemoral pain syndrome Osteochondritis dissecans *Patellar or quadriceps tendonitis Fat pad hypertrophy/impingement (Hoffa's disease) Patellar stress fracture Prepatellar or infrapatellar bursitis Referred pain Adapted with permission from Patel DR, Nelson TL. Sports injuries in adolescents. Med Clin North Am 2000;84:

17 Epidemiology of Apophysitis Knee Injuries in Adolescents Osgood Schlatter disease(osd) -Prevalence athletic adolescents 21% vs. 4.5% of age matched nonathletes -Age of onset: Girls 8-13 Boys Boys > Girls, equalizing -Bilateral in 20% Sinding-Larsen-Johansson disease(sld) -Prevalence athletic adolescents unkown, but 10-20% coexist with OSD -Age of onset-similar to OSD -Boys > Girls

18 Diagnostic testing of Apophysitis of the knee Clinical diagnosis-if the history and physical exam indicate OSD or SLD radiographs are not needed.

19 Treatment-Apophysitis and Patellar Tendonitis OSD Patellar tendonitis SLD 1. Cross training 1. Cross training 1. Cross training 2. Ice massage 2. Ice massage 2. Ice massage 3. Hamstring & 3. Hamstring & 3. Hamstring & Quad stretching Quad stretching Quad stretching 4. Tibial tubercle 4. Cho-pat strap 4. Patellar knee Padded neoprene 5. NSAIDs prn neoprene sleeve Sleeve 6. Orthotics 5. NSAIDs prn 5. NSAIDs prn 6. Orthotics 6. Assess feetorthotics

20 Cho-pat strap

21 Complications of Apophysitis Painful kneeling-60% of all OSD patients have chronic pain on hitting tibial tuberosity Painless bump over tibial tuberosity-most, benign Painful distal or proximal patellar tendon insertion or avulsion of tibial tubercle - surgical removal (rare)

22 Case 3 14 year old female basketball player c/o knee pain after sudden fall to floor. No contact or trauma occurs to the knee. She heard a pop. She is still growing and is currently going through puberty w/o menses yet. Her knee is acutely swollen. On examination: Inspection: + effusion Special tests: + Anterior drawer and + Lachmans. Remainder of testing difficult due to swelling.

23 Physical Exam of Anterior Cruciate Ligament

24 Epidemiology of ACL injuriesepidemic in woman athletes 80, ,000 ACL injuries per year in young athlete (15-25 years of age) More common in woman than in men Non-contact mechanism much more common in woman and in jumping and quick starting and stopping sports (basketball, soccer, etc.)

25 Why is an ACL tear an epidemic in woman in sports? Risk factors in woman 1. Anatomy-smaller femoral notch width (bony impingement or houses smaller ACL?) and ACL size is smaller in woman 2. Hormonal effects-estrogen and progesterone receptors on ACL. Higher levels decreases collagen synthesis of ACL fibroblasts

26 Why is an ACL tear an epidemic in woman in sports? 3. Environmental-improper shoes (cross trainers) and improper jumping technique 4. Biomechanical- Ligamentous laxity of ACL and limb alignment with greater Q angle (miserable malalignment syndrome)

27 Physes of immature knee Distal femoral and proximal tibial physes account for 65% of lower extremity growth MRI evaluation of physes -0% closed at 11 years -5% at 12 yrs -34% at 13 yrs -53% at 14 yrs -94% at 15 yrs -100% at 16 yrs *girls earlier than boys

28 Evaluation of skeletal maturity An accurate assessment of skeletal maturity aids in discussing risks and benefits of operative and nonoperative treatment options. -Tanner staging -Radiographs of the hand and knee -Timing of adolescent growth spurt -Onset of menses -Comparison of parental height

29 Treatment Midsubstance Tears -Non-operative treatment-traditionally accepted as standard 1. Activity modification: no cutting or stop/start activities 2. Physical therapy 3. Bracing 4. Monitor until skeletal maturity-once reaches skeletal maturity, then operative ACL reconstruction

30 Return to play-to brace or not to brace Derotational braces by most authorities in Sports Medicine are thought as simply psychological aids to recovery. -Problems: Difficult to properly fit No Evidence based studies to support

31 Treatment Problem: Adolescent population by nature is active and commonly suffers other injuries due to an unstable knee -Multiple studies have shown increased rates of meniscal tears, chondral injuries, and early degenerative arthritis *Graf et al, Arthroscopy, 1992 and Pressman et al, J Ped Ortho, 1997.

32 Treatment -Alternative treatment: Transphyseal, soft tissue allograft (patellar tendon) reconstruction. Concern: Growth abnormalities One study of 16 pts Tanner stage 3 or 4 showed all athletes returned to competitive athletics w/o growth abnormalities *Shelbourne et al, AJSM, 2004.

33 ACL injury prevention programs Prevention Programs: combine proper jumping, landing and cutting techniques for athletes while providing strength training, flexibility, plyometrics and sports specific exercises. -Baystate, Massachusetts-Jump Program -University of Michigan-Leap program -California Prevention Injury and Enhance Performance Program (PEP)-17 minutes

34 Case 4 JL is a 15 yo boy w/ acute onset of R knee pain and swelling x 1 day -Tackled in football, knee twisted and he heard a pop -Denies knee giving out under him -On exam had effusion and right thigh atrophy over VMO. Tenderness over medial femoral condyle. Decreased ROM as could flex only 45 degrees. Remainder of exam (including ligament testing) was normal. -PMH- Knee injury 1 year ago.

35 Osteochondritis Dissecans of the Knee(OCD)-Epidemiology Most common in yr olds in sports Most common site is medial femoral condyle Likely secondary to avascular necrosis of subchondral bone from multifactorial causes (trauma, repetitive impact to tibial spine, abnormal ossification of epiphyseal cartilage)

36 Clinical Findings of OCD Physical exam often inconclusive. Most consistent finding is thigh atrophy secondary to lack of use and de-conditioning. With floating bodies, can develop locking, catching, pain and effusion Meniscal tests are frequently positive due to the asymmetry of the joint and the compensation by the athlete for the pain.

37 OCD-Diagnostic testing X-rays of the knee- Testing of choice for screening for boney injury secondary to trauma. *Radiographic testing via AP, lateral, and tunnel view of knee

38 Pittsburgh and Ottawa Knee rules Pittsburgh decision rules 1. Blunt trauma or a fall as mechanism of injury plus either of the following: A. Age younger than 12 years or older than 50 years and/or B. Inability to walk four weight-bearing steps in the ER Ottawa Knee rules 1. Age 55 or over 2. Isolated tenderness of the patella 3. Tenderness at the head of the fibula 4. Inability to flex to 90 degrees 5. Inability to weight bear both immediately and in the ER (4 steps)

39 Staging of OCD Lesions MRI- test of choice to stage severity of OCD. Early Referral is key to orthopedic surgeon to help prevent further meniscal damage and premature arthritis.

40 Treatment of OCD Stage Age Sign/symptoms Treatment pain w/o mech activity mod until pain gone, acute symptoms F/U in 3-6 mo, re-eval if pain chronic pain, Activity rest., crutch use, cast, chronic effusion arthroscopy with revasc drilling chronic pain, catch, Arthroscopy for removal osteo osteo body lock, giving way body, no wt bear 6-12 wks, rehab in situ chronic pain, catch, Arthroscopy for removal of loose loose body lock, giving way body, no wt bear for 3 mo, rehab

41 Take Home Points 1. PFKD-most common knee injury in adolescents. 2. If the history and physical exam indicate OSD, SLD, or Patellar tendonitis radiographs are not needed. 3. An accurate assessment of skeletal maturity aids in discussing risks and benefits of operative and nonoperative treatment options in ACL injuries. 4. ACL Prevention Programs combine proper jumping, landing and cutting techniques for athletes while providing strength training, flexibility, plyometrics and sports specific exercises. 5. Utilize the Pittsburgh or Ottawa knee rules to determine when to obtain radiographs of knee injuries.